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| Publications of Stefan Zauscher :chronological alphabetical combined listing:
%% Papers Published
@article{fds369714,
Author = {Young, MN and Sindoni, MJ and Lewis, AH and Zauscher, S and Grandl,
J},
Title = {The energetics of rapid cellular mechanotransduction.},
Journal = {Proc Natl Acad Sci U S A},
Volume = {120},
Number = {8},
Pages = {e2215747120},
Year = {2023},
Month = {February},
url = {http://dx.doi.org/10.1073/pnas.2215747120},
Abstract = {Cells throughout the human body detect mechanical forces.
While it is known that the rapid (millisecond) detection of
mechanical forces is mediated by force-gated ion channels, a
detailed quantitative understanding of cells as sensors of
mechanical energy is still lacking. Here, we combine atomic
force microscopy with patch-clamp electrophysiology to
determine the physical limits of cells expressing the
force-gated ion channels (FGICs) Piezo1, Piezo2, TREK1, and
TRAAK. We find that, depending on the ion channel expressed,
cells can function either as proportional or nonlinear
transducers of mechanical energy and detect mechanical
energies as little as ~100 fJ, with a resolution of up to ~1
fJ. These specific energetic values depend on cell size,
channel density, and cytoskeletal architecture. We also make
the surprising discovery that cells can transduce forces
either nearly instantaneously (<1 ms) or with a substantial
time delay (~10 ms). Using a chimeric experimental approach
and simulations, we show how such delays can emerge from
channel-intrinsic properties and the slow diffusion of
tension in the membrane. Overall, our experiments reveal the
capabilities and limits of cellular mechanosensing and
provide insights into molecular mechanisms that different
cell types may employ to specialize for their distinct
physiological roles.},
Doi = {10.1073/pnas.2215747120},
Key = {fds369714}
}
@article{fds362173,
Author = {Simon, M and Prause, A and Zauscher, S and Gradzielski,
M},
Title = {Self-Assembled Single-Stranded DNA Nano-Networks in Solution
and at Surfaces.},
Journal = {Biomacromolecules},
Volume = {23},
Number = {3},
Pages = {1242-1250},
Year = {2022},
Month = {March},
url = {http://dx.doi.org/10.1021/acs.biomac.1c01493},
Abstract = {We studied the directed self-assembly of two types of
complementary single-stranded DNA (ssDNA) strands [i.e.,
poly(dA) and poly(dT)] into more complex, organized, and
percolating networks in dilute solutions and at surfaces.
Understanding ssDNA self-assembly into 2D networks on
surfaces is important for the use of such networks in the
fabrication of well-defined nanotechnological devices, as,
for instance, required in nanoelectronics or for biosensing.
To control the formation of 2D networks on surfaces, it is
important to know whether DNA assemblies are formed already
in dilute solutions or only during the drying/immobilization
process at the surface, where the concentration
automatically increases. Fluorescence cross-correlation
spectroscopy clearly shows the presence of larger DNA
complexes in mixed poly(dA) and poly(dT) solutions already
at very low DNA concentrations (<1 nM), that is, well below
the overlap concentration. Here, we describe for the first
time such supramolecular complexes in solution and how their
structure depends on the ssDNA length and concentration and
ionic strength. Hence, future attempts to control such
networks should also focus on network precursors in solution
and not only on their immobilization on surfaces.},
Doi = {10.1021/acs.biomac.1c01493},
Key = {fds362173}
}
@article{fds359628,
Author = {Gilpin, A and Zeng, Y and Hoque, J and Ryu, JH and Yang, Y and Zauscher, S and Eward, W and Varghese, S},
Title = {Self-Healing of Hyaluronic Acid to Improve In Vivo Retention
and Function.},
Journal = {Adv Healthc Mater},
Volume = {10},
Number = {23},
Pages = {e2100777},
Year = {2021},
Month = {December},
url = {http://dx.doi.org/10.1002/adhm.202100777},
Abstract = {Convergent advances in the field of soft matter,
macromolecular chemistry, and engineering have led to the
development of biomaterials that possess autonomous,
adaptive, and self-healing characteristics similar to living
systems. These rationally designed biomaterials can surpass
the capabilities of their parent material. Herein, the
modification of hyaluronic acid (HA) to exhibit self-healing
properties is described, and its physical and biological
function both in vitro and in vivo is studied. The in vitro
findings showed that self-healing HA designed to undergo
self-repair improves lubrication, enhances free radical
scavenging, and attenuates enzymatic degradation compared to
unmodified HA. Longitudinal imaging following intraarticular
injection of self-healing HA shows improved in vivo
retention despite its low molecular weight. Concomitant with
these functions, intraarticular injection of self-healing HA
mitigates anterior cruciate ligament injury-mediated
cartilage degeneration in rodents. This proof-of-concept
study shows how incorporation of functional properties such
as self-healing can be used to surpass the existing
capabilities of biolubricants.},
Doi = {10.1002/adhm.202100777},
Key = {fds359628}
}
@article{fds358984,
Author = {Yang, Y and Lu, Q and Huang, C-M and Qian, H and Zhang, Y and Deshpande, S and Arya, G and Ke, Y and Zauscher, S},
Title = {Programmable Site-Specific Functionalization of DNA Origami
with Polynucleotide Brushes.},
Journal = {Angewandte Chemie International Edition},
Volume = {60},
Number = {43},
Pages = {23241-23247},
Publisher = {WILEY},
Year = {2021},
Month = {October},
url = {http://dx.doi.org/10.1002/anie.202107829},
Abstract = {Combining surface-initiated, TdT (terminal deoxynucleotidyl
transferase) catalyzed enzymatic polymerization (SI-TcEP)
with precisely engineered DNA origami nanostructures (DONs)
presents an innovative pathway for the generation of stable,
polynucleotide brush-functionalized DNA nanostructures. We
demonstrate that SI-TcEP can site-specifically pattern DONs
with brushes containing both natural and non-natural
nucleotides. The brush functionalization can be precisely
controlled in terms of the location of initiation sites on
the origami core and the brush height and composition.
Coarse-grained simulations predict the conformation of the
brush-functionalized DONs that agree well with the
experimentally observed morphologies. We find that
polynucleotide brush-functionalization increases the
nuclease resistance of DONs significantly, and that this
stability can be spatially programmed through the
site-specific growth of polynucleotide brushes. The ability
to site-specifically decorate DONs with brushes of natural
and non-natural nucleotides provides access to a large range
of functionalized DON architectures that would allow for
further supramolecular assembly, and for potential
applications in smart nanoscale delivery
systems.},
Doi = {10.1002/anie.202107829},
Key = {fds358984}
}
@article{fds358983,
Author = {Navarro, LA and Ryan, JJ and Dzuricky, M and Gradzielski, M and Chilkoti, A and Zauscher, S},
Title = {Microphase Separation of Resilin-like and Elastin-like
Diblock Copolypeptides in Concentrated Solutions.},
Journal = {Biomacromolecules},
Volume = {22},
Number = {9},
Pages = {3827-3838},
Year = {2021},
Month = {September},
url = {http://dx.doi.org/10.1021/acs.biomac.1c00672},
Abstract = {Diblock copolymers are valued for their ability to form thin
films with nanoscale features that typically reflect those
of their microphase-separated structures in concentrated
solution. Here, we show that such self-assembled structures
can be easily formed with diblock copolymers composed of
thermally responsive polypeptides, such as resilin-like
polypeptides (RLP) and elastin-like polypeptides (ELP), by
exploiting the inverse temperature transition behavior of
ELPs in aqueous media. Specifically, we examine the
self-assembly of a series of RLP-<i>b</i>-ELP diblock
copolypeptides in concentrated aqueous solution (30 and 50
wt %) by small-angle X-ray scattering (SAXS). By
systematically varying RLP block length and temperature
(10-45 °C), we observed microphase separation into
hexagonally packed cylinders and lamellae. By analyzing the
observed order-order transitions (OOT) and order-disorder
transitions (ODT), we determined that self-assembly in this
system is primarily driven by polymer-solvent interactions.
While these thermally responsive polymers showed clear ODTs
and OOTs at certain temperatures, temperature only had a
weak effect on the spacing of the resulting nanostructures.
In contrast, we found that nanostructure spacing was far
more sensitive to RLP block length. Finally, we used atomic
force microscopy (AFM) to demonstrate that spin casting
RLP-<i>b</i>-ELP diblock copolypeptides also produce
nanostructured thin films with spacings that correlate with
those in concentrated solution.},
Doi = {10.1021/acs.biomac.1c00672},
Key = {fds358983}
}
@article{fds354600,
Author = {Walkowiak, J and Gradzielski, M and Zauscher, S and Ballauff,
M},
Title = {Interaction of Proteins with a Planar Poly(acrylic acid)
Brush: Analysis by Quartz Crystal Microbalance with
Dissipation Monitoring (QCM-D).},
Journal = {Polymers},
Volume = {13},
Number = {1},
Pages = {E122},
Year = {2020},
Month = {December},
url = {http://dx.doi.org/10.3390/polym13010122},
Abstract = {We describe the preparation of a poly(acrylic acid) (PAA)
brush, polymerized by atom transfer radical polymerization
(ATRP) of tert-butyl acrylate (tBA) and subsequent acid
hydrolysis, on the flat gold surfaces of quartz-crystal
microbalance (QCM) crystals. The PAA brushes were
characterized by Fourier transform infrared (FT-IR)
spectroscopy, ellipsometry and water contact angle analysis.
The interaction of the PAA brushes with human serum albumin
(HSA) was studied for a range of ionic strengths and pH
conditions by quartz-crystal microbalance with dissipation
monitoring (QCM-D). The quantitative analysis showed a
strong adsorption of protein molecules onto the PAA brush.
By increasing the ionic strength, we were able to release a
fraction of the initially bound HSA molecules. This finding
highlights the importance of counterions in the
polyelectrolyte-mediated protein adsorption/desorption. A
comparison with recent calorimetric studies related to the
binding of HSA to polyelectrolytes allowed us to fully
analyze the QCM data based on the results of the
thermodynamic analysis of the binding process.},
Doi = {10.3390/polym13010122},
Key = {fds354600}
}
@article{fds351487,
Author = {Fries, CN and Wu, Y and Kelly, SH and Wolf, M and Votaw, NL and Zauscher,
S and Collier, JH},
Title = {Controlled Lengthwise Assembly of Helical Peptide Nanofibers
to Modulate CD8+ T-Cell Responses.},
Journal = {Advanced Materials (Deerfield Beach, Fla.)},
Volume = {32},
Number = {39},
Pages = {e2003310},
Year = {2020},
Month = {October},
url = {http://dx.doi.org/10.1002/adma.202003310},
Abstract = {Peptide nanofibers are useful for many biological
applications, including immunotherapy, tissue engineering,
and drug delivery. The robust lengthwise assembly of these
peptides into nanofibers is typically difficult to control,
resulting in polydisperse fiber lengths and an incomplete
understanding of how nanofiber length affects biological
responses. Here, rationally designed capping peptides
control the length of helical peptide nanofibers with unique
precision. These designed peptides bind the tips of
elongated nanofibers to shorten and narrow their length
distributions. Demonstrating their use as immunotherapies,
capped nanofibers are preferentially cross-presented by
dendritic cells compared to uncapped nanofibers. Due to
increased cross-presentation, these capped nanofibers
trigger stronger CD8<sup>+</sup> T-cell responses in mice
than uncapped nanofibers. This strategy illustrates a means
for controlling the length of supramolecular peptide
nanofibers to modulate their immunogenicity in the context
of immunotherapies.},
Doi = {10.1002/adma.202003310},
Key = {fds351487}
}
@article{fds352662,
Author = {Noyce, SG and Doherty, JL and Zauscher, S and Franklin,
AD},
Title = {Understanding and Mapping Sensitivity in MoS2
Field-Effect-Transistor-Based Sensors.},
Journal = {Acs Nano},
Volume = {14},
Number = {9},
Pages = {11637-11647},
Year = {2020},
Month = {September},
url = {http://dx.doi.org/10.1021/acsnano.0c04192},
Abstract = {Sensors based on two-dimensional (2D) field-effect
transistors (FETs) are extremely sensitive and can detect
charged analytes with attomolar limits of detection (LOD).
Despite some impressive LODs, the operating mechanisms and
factors that determine the signal-to-noise ratio in 2D
FET-based sensors remain poorly understood. These
uncertainties, coupled with an expansive design space for
sensor layout and analyte positioning, result in a field
with many reported highlights but limited collective
progress. Here, we provide insight into sensing mechanisms
of 2D molybdenum disulfide (MoS<sub>2</sub>) FETs by
realizing precise control over the position and charge of an
analyte using a customized atomic force microscope (AFM),
with the AFM tip acting as an analyte. The sensitivity of
the MoS<sub>2</sub> FET channel is revealed to be
nonuniform, manifesting sensitive hotspots with locations
that are stable over time. When the charge of the analyte is
varied, an asymmetry is observed in the device drain-current
response, with analytes acting to turn the device off
leading to a 2.5× increase in the signal-to-noise ratio
(SNR). We developed a numerical model, applicable to all
FET-based charge-detection sensors, that confirms our
experimental observation and suggests an underlying
mechanism. Further, extensive characterization of a set of
different MoS<sub>2</sub> FETs under various analyte
conditions, coupled with the numerical model, led to the
identification of three distinct SNRs that peak with
dependence on the layout and operating conditions used for a
sensor. These findings reveal the important role of analyte
position and coverage in determining the optimal operating
bias conditions for maximal sensitivity in 2D FET-based
sensors, which provides key insights for future sensor
design and control.},
Doi = {10.1021/acsnano.0c04192},
Key = {fds352662}
}
@article{fds349645,
Author = {Navarro, LA and Shah, TP and Zauscher, S},
Title = {Grafting To of Bottlebrush Polymers: Conformation and
Kinetics.},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {36},
Number = {17},
Pages = {4745-4756},
Year = {2020},
Month = {May},
url = {http://dx.doi.org/10.1021/acs.langmuir.9b03620},
Abstract = {Specifically adsorbed bottlebrush coatings are found in
nature as brush-like glycoproteins that decorate
biointerfaces and provide antifouling, lubrication, or
wear-protection. Although various synthetic strategies have
been developed to mimic glycoprotein structure and function,
the use of these mimics is still limited because of the
current lack of understanding of their adsorption behavior
and surface conformation. In this paper, we examine the
adsorption behavior of PEG-based, biotinylated bottlebrushes
with different backbone and bristle lengths to streptavidin
model surfaces in phosphate-buffered saline. By using quartz
crystal microbalance, localized surface plasmon resonance,
and atomic force microscopy, we learn how bottlebrush
dimensions impact their adsorption kinetics, surface
conformation, mechanical properties, and antifouling
properties. Our bottlebrushes qualitatively mirror the
adsorption behavior of linear polymers and exhibit three
kinetic regimes of adsorption: (I) a transport-limited
regime, (II) a pause, and (III) a penetration-limited
regime. Furthermore, we find that the bristle length more
dramatically affects brush properties than the backbone
length. Generally, larger bottlebrush dimensions lead to
reduced molar adsorption, retarded kinetics, weaker
antifouling, and softer brush coatings. Longer bristles also
lead to less mass adsorption, while the opposite trend is
observed for increasing backbone length. In summary, our
findings aid the rational design of new bottlebrush coatings
by elucidating how their dimensions impact adsorption,
surface conformation, and the properties of the final
coating.},
Doi = {10.1021/acs.langmuir.9b03620},
Key = {fds349645}
}
@article{fds348734,
Author = {Zhou, Y and Maleski, K and Anasori, B and Thostenson, JO and Pang, Y and Feng, Y and Zeng, K and Parker, CB and Zauscher, S and Gogotsi, Y and Glass, JT and Cao, C},
Title = {Ti3C2Tx MXene-Reduced Graphene Oxide Composite Electrodes
for Stretchable Supercapacitors.},
Journal = {Acs Nano},
Volume = {14},
Number = {3},
Pages = {3576-3586},
Year = {2020},
Month = {March},
url = {http://dx.doi.org/10.1021/acsnano.9b10066},
Abstract = {The development of stretchable electronics requires the
invention of compatible high-performance power sources, such
as stretchable supercapacitors and batteries. In this work,
two-dimensional (2D) titanium carbide (Ti3C2Tx) MXene is
being explored for flexible and printed energy storage
devices by fabrication of a robust, stretchable
high-performance supercapacitor with reduced graphene oxide
(RGO) to create a composite electrode. The Ti3C2Tx/RGO
composite electrode combines the superior electrochemical
and mechanical properties of Ti3C2Tx and the mechanical
robustness of RGO resulting from strong nanosheet
interactions, larger nanoflake size, and mechanical
flexibility. It is found that the Ti3C2Tx/RGO composite
electrodes with 50 wt % RGO incorporated prove to mitigate
cracks generated under large strains. The composite
electrodes exhibit a large capacitance of 49 mF/cm2 (∼490
F/cm3 and ∼140 F/g) and good electrochemical and
mechanical stability when subjected to cyclic uniaxial
(300%) or biaxial (200% × 200%) strains. The as-assembled
symmetric supercapacitor demonstrates a specific capacitance
of 18.6 mF/cm2 (∼90 F/cm3 and ∼29 F/g) and a
stretchability of up to 300%. The developed approach offers
an alternative strategy to fabricate stretchable MXene-based
energy storage devices and can be extended to other members
of the large MXene family.},
Doi = {10.1021/acsnano.9b10066},
Key = {fds348734}
}
@article{fds348924,
Author = {Roberts, S and Miao, V and Costa, S and Simon, J and Kelly, G and Shah, T and Zauscher, S and Chilkoti, A},
Title = {Complex microparticle architectures from stimuli-responsive
intrinsically disordered proteins.},
Journal = {Nature Communications},
Volume = {11},
Number = {1},
Pages = {1342},
Year = {2020},
Month = {March},
url = {http://dx.doi.org/10.1038/s41467-020-15128-9},
Abstract = {The controllable production of microparticles with complex
geometries is useful for a variety of applications in
materials science and bioengineering. The formation of
intricate microarchitectures typically requires
sophisticated fabrication techniques such as flow
lithography or multiple-emulsion microfluidics. By
harnessing the molecular interactions of a set of artificial
intrinsically disordered proteins (IDPs), we have created
complex microparticle geometries, including porous
particles, core-shell and hollow shell structures, and a
unique 'fruits-on-a-vine' arrangement, by exploiting the
metastable region of the phase diagram of thermally
responsive IDPs within microdroplets. Through multi-site
unnatural amino acid (UAA) incorporation, these protein
microparticles can also be photo-crosslinked and stably
extracted to an all-aqueous environment. This work expands
the functional utility of artificial IDPs as well as the
available microarchitectures of this class of biocompatible
IDPs, with potential applications in drug delivery and
tissue engineering.},
Doi = {10.1038/s41467-020-15128-9},
Key = {fds348924}
}
@article{fds358985,
Author = {Kim, HS and Brown, NA and Zauscher, S and Yingling,
YG},
Title = {Effect of Octadecylamine Surfactant on DNA Interactions with
Graphene Surfaces.},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {36},
Number = {4},
Pages = {931-938},
Year = {2020},
Month = {February},
url = {http://dx.doi.org/10.1021/acs.langmuir.9b02926},
Abstract = {Understanding of how to integrate DNA molecules with
graphene materials is important for the development of
biosensors and biomolecular logic circuits. For some of
these applications, controlling DNA structural conformation
on the graphene substrate is critically important and can be
achieved through the use of self-assembled monolayers. Here,
we performed all-atom molecular dynamics simulations to
understand how various 1-octadecylamine (ODA) coatings of
the graphene surface affect the conformation of
double-stranded DNA (dsDNA) on the surface. The simulation
results demonstrated that dsDNA structures become more
stable as ODA concentration increases due to the formation
of DNA-ODA hydrogen bonds and reduction of DNA-surface
interactions, which aid in retaining internal DNA
interactions. Specifically, the interaction of ODA molecules
with DNA prevents nucleobases from forming π-π stacking
interactions with the surface. Some dsDNA conformations,
such as sharp kinks or unwinding, can occur more frequently
in DNA with A-T sequences due to weaker pairing interactions
than with G-C sequences. Furthermore, our results conclude
that both DNA sequence and ODA concentration play an
essential role in experimentally observed conformational
changes of DNA on the graphene surface.},
Doi = {10.1021/acs.langmuir.9b02926},
Key = {fds358985}
}
@article{fds347038,
Author = {Walkowiak, J and Lu, Y and Gradzielski, M and Zauscher, S and Ballauff,
M},
Title = {Thermodynamic Analysis of the Uptake of a Protein in a
Spherical Polyelectrolyte Brush.},
Journal = {Macromolecular Rapid Communications},
Volume = {41},
Number = {1},
Pages = {e1900421},
Year = {2020},
Month = {January},
url = {http://dx.doi.org/10.1002/marc.201900421},
Abstract = {A thermodynamic study of the adsorption of Human Serum
Albumin (HSA) onto spherical polyelectrolyte brushes (SPBs)
by isothermal titration calorimetry (ITC) is presented. The
SPBs are composed of a solid polystyrene core bearing long
chains of poly(acrylic acid). ITC measurements done at
different temperatures and ionic strengths lead to a full
set of thermodynamicbinding constants together with the
enthalpies and entropies of binding. The adsorption of HSA
onto SPBs is described with a two-step model. The free
energy of binding ΔGb depends only weakly on temperature
because of a marked compensation of enthalpy by entropy.
Studies of the adsorbed HSA by Fourier transform infrared
spectroscopy (FT-IR) demonstrate no significant disturbance
in the secondary structure of the protein. The quantitative
analysis demonstrates that counterion release is the major
driving force for adsorption in a process where proteins
become multivalent counterions of the polyelectrolyte chains
upon adsorption. A comparison with the analysis of other
sets of data related to the binding of HSA to
polyelectrolytes demonstrates that the cancellation of
enthalpy and entropy is a general phenomenon that always
accompanies the binding of proteins to polyelectrolytes
dominated by counterion release.},
Doi = {10.1002/marc.201900421},
Key = {fds347038}
}
@article{fds345459,
Author = {Eldridge, WJ and Ceballos, S and Shah, T and Park, HS and Steelman, ZA and Zauscher, S and Wax, A},
Title = {Shear Modulus Measurement by Quantitative Phase Imaging and
Correlation with Atomic Force Microscopy.},
Journal = {Biophysical Journal},
Volume = {117},
Number = {4},
Pages = {696-705},
Year = {2019},
Month = {August},
url = {http://dx.doi.org/10.1016/j.bpj.2019.07.008},
Abstract = {Many approaches have been developed to characterize cell
elasticity. Among these, atomic force microscopy (AFM)
combined with modeling has been widely used to characterize
cellular compliance. However, such approaches are often
limited by the difficulties associated with using a specific
instrument and by the complexity of analyzing the measured
data. More recently, quantitative phase imaging (QPI) has
been applied to characterize cellular stiffness by using an
effective spring constant. This metric was further
correlated to mass distribution (disorder strength) within
the cell. However, these measurements are difficult to
compare to AFM-derived measurements of Young's modulus.
Here, we describe, to our knowledge, a new way of analyzing
QPI data to directly retrieve the shear modulus. Our
approach enables label-free measurement of cellular
mechanical properties that can be directly compared to
values obtained from other rheological methods. To
demonstrate the technique, we measured shear modulus and
phase disorder strength using QPI, as well as Young's
modulus using AFM, across two breast cancer cell-line
populations dosed with three different concentrations of
cytochalasin D, an actin-depolymerizing toxin. Comparison of
QPI-derived and AFM moduli shows good agreement between the
two measures and further agrees with theory. Our results
suggest that QPI is a powerful tool for cellular biophysics
because it allows for optical quantitative measurements of
cell mechanical properties.},
Doi = {10.1016/j.bpj.2019.07.008},
Key = {fds345459}
}
@article{fds358986,
Author = {Sokolowski, M and Parlak, Z and Bartsch, C and Zauscher, S and Gradzielski, M},
Title = {Interaction between Soft Nanoparticles and Phospholipid
Membranes: Effect of the Polymer-Grafting Density on
Nanoparticle Adsorption},
Journal = {Acs Applied Nano Materials},
Volume = {2},
Number = {4},
Pages = {1808-1819},
Year = {2019},
Month = {April},
url = {http://dx.doi.org/10.1021/acsanm.8b01868},
Abstract = {Nanoparticles (NPs) have large potential for biological
applications as typically they exhibit strongly
size-dependent properties. Specifically, the interaction of
NPs with phospholipid membranes is of significant relevance
to nanomedicine and the related field of nanotoxicology.
Therefore, the investigation of NP interactions with model
membranes is not only of fundamental importance but also of
practical value to understand NP interactions with more
complex cell membranes. Supported lipid bilayers (SLBs)
provide a powerful platform to study such interactions.
Here, we report on the interaction of SiO2-NPs, covered with
cationic polymer (PDMAEMA) of different grafting density but
approximately constant polymer layer thickness, with SLBs of
differing charge density. We studied binding of the NPs to
the SLBs by quartz crystal microbalance with dissipation
monitoring (QCM-D) and atomic force microscopy (AFM). A key
result of the study is that at low solution pH and in the
presence of electrostatic attraction, the amount of adsorbed
NPs drastically decreases with increasing polymer brush
grafting density beyond a critical value. However, upon
increasing the solution pH (thereby lowering the apparent
electrostatic attraction) even NPs with high polymer
grafting density adsorb. In this transitional range, NP
adsorption depends strongly on NP concentration becoming
reduced at higher concentration. The experimental
observations were interpreted by simple models taking into
account electrostatic and van der Waals interactions that
allow to gain some insights into the prevailing
conditions.},
Doi = {10.1021/acsanm.8b01868},
Key = {fds358986}
}
@article{fds341550,
Author = {Navarro, LA and Enciso, AE and Matyjaszewski, K and Zauscher,
S},
Title = {Enzymatically Degassed Surface-Initiated Atom Transfer
Radical Polymerization with Real-Time Monitoring.},
Journal = {Journal of the American Chemical Society},
Volume = {141},
Number = {7},
Pages = {3100-3109},
Year = {2019},
Month = {February},
url = {http://dx.doi.org/10.1021/jacs.8b12072},
Abstract = {Polymer brush coatings are frequently prepared by radical
polymerization, a notoriously oxygen sensitive process.
Glucose oxidase (GOx) can inexpensively enable radical
polymerization in solution by enzymatically consuming oxygen
as it oxidizes glucose. Here, we report the growth of
polymeric brushes using GOx-assisted atom transfer radical
polymerization (ATRP) from a surface while open to air.
Specifically, we grew a set of biomedically relevant polymer
brushes, including poly(oligo(ethylene glycol) methacrylate)
(POEGMA), poly(2-dimethylaminoethyl methacrylate) (PDMAEMA),
poly(sulfobetaine methacrylate) (PSBMA), and
poly(2-(methylsulfinyl)ethyl acrylate (PMSEA). For each of
these polymers, we monitored GOx-assisted and GOx-free ATRP
reaction kinetics in real time using quartz crystal
microbalance (QCM) and verified findings with localized
surface plasmon resonance (LSPR). We modeled brush growth
kinetics considering bimolecular termination. This model fit
our data well ( r<sup>2</sup> > 0.987 for all samples) and
shows the addition of GOx increased effective kinetic chain
lengths, propagation rates, and reproducibility. We tested
the antifouling properties of the polymer brush coatings
against human blood plasma and were surprised to find that
coatings prepared with GOx repelled more plasma proteins in
all cases than their GOx-free counterparts.},
Doi = {10.1021/jacs.8b12072},
Key = {fds341550}
}
@article{fds339660,
Author = {Navarro, LA and French, DL and Zauscher, S},
Title = {Advances in mucin mimic synthesis and applications in
surface science},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {38},
Pages = {122-134},
Publisher = {Elsevier BV},
Year = {2018},
Month = {November},
url = {http://dx.doi.org/10.1016/j.cocis.2018.09.004},
Abstract = {Mucins are a class of glycoproteins that serve key roles in
tissue protection, hydration, and lubrication. However,
their study and application are complicated by their
post-translational modifications, heterogeneity, and their
propensity to deteriorate upon isolation. As a result,
several groups have made strides in synthesizing
mucin-mimicking compounds for systematic study and
therapeutic applications. In this paper, we review general
mucin structure, recent trends in the design and synthesis
of mucin mimics, and the ways mucin analogues can outperform
native mucins. Specifically, we highlight the structures of
lubricin and aggrecan, which are the subject of many
biomimetic approaches. Furthermore, we showcase the
structural features that allow analogues to mimic mucin
functions and categorize them based on their roles as
monolayer coatings, gel formers, or adhesion promoters.
Lastly, we examine the chemical composition of mucin
analogues, emphasizing how modular approaches provide
flexibility to repurpose mucin mimics for different
applications.},
Doi = {10.1016/j.cocis.2018.09.004},
Key = {fds339660}
}
@article{fds340146,
Author = {Feng, Y and Marusak, KE and You, L and Zauscher, S},
Title = {Biosynthetic transition metal chalcogenide semiconductor
nanoparticles: Progress in synthesis, property control and
applications},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {38},
Pages = {190-203},
Publisher = {Elsevier BV},
Year = {2018},
Month = {November},
url = {http://dx.doi.org/10.1016/j.cocis.2018.11.002},
Abstract = {Transition metal (TM) chalcogenides are a group of
semiconductor materials with applications that range from
antibacterial particles to thin films in energy conversion
devices. Significant progress in synthetic biology combined
with the benefits of low energy consumption and low toxic
waste burden of “green synthesis,” have directed
considerable research attention to the biosynthesis of these
inorganic materials. TM chalcogenide nanoparticles (NP) can
be produced by a variety of microorganisms including
bacteria, fungi, algae, and yeast, as well as cell-free
approaches using enzymes. Recent research shows that the
size, crystal structure, and bandgap of these TM NPs can be
well controlled, which has led to prototypical applications
of these biosynthetic NPs in the areas of bio-remediation,
bio-imaging, photocatalysis, and energy conversion. This
review is the first to combine recent progress in the
biosynthesis, property control, and applications of TM
chalcogenide NPs.},
Doi = {10.1016/j.cocis.2018.11.002},
Key = {fds340146}
}
@article{fds340147,
Author = {Malmsten, M and Zauscher, S},
Title = {Editorial overview: Colloids and surfaces in
biology},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {38},
Pages = {A1-A3},
Publisher = {Elsevier BV},
Year = {2018},
Month = {November},
url = {http://dx.doi.org/10.1016/j.cocis.2018.11.006},
Doi = {10.1016/j.cocis.2018.11.006},
Key = {fds340147}
}
@article{fds327223,
Author = {Rastogi, SK and Anderson, HE and Lamas, J and Barret, S and Cantu, T and Zauscher, S and Brittain, WJ and Betancourt, T},
Title = {Enhanced Release of Molecules upon Ultraviolet (UV) Light
Irradiation from Photoresponsive Hydrogels Prepared from
Bifunctional Azobenzene and Four-Arm Poly(ethylene
glycol).},
Journal = {Acs Applied Materials & Interfaces},
Volume = {10},
Number = {36},
Pages = {30071-30080},
Year = {2018},
Month = {September},
url = {http://dx.doi.org/10.1021/acsami.6b16183},
Abstract = {Advances in biosensors and drug delivery are dependent on
hydrogels that respond to external stimuli. In this work, we
describe the preparation and characterization of
photoresponsive hydrogels prepared by cross-linking of
di-NHS ester of azobenzoic acid and four-armed,
amine-terminated poly(ethylene glycol). The porous structure
and composition of the hydrogels were confirmed by scanning
electron microscopy (SEM) and Fourier transform infrared
(FTIR) spectroscopy. The reversible photoisomerization of
the azobenzene-containing hydrogel cross-linkers in the gels
was confirmed by absorption spectroscopy. Specifically, the
photoisomerization of the cross-linkers between their trans
and cis configurations was observed by monitoring the
absorbance of the hydrogels at the two characteristic peaks
of azobenzene (π-π* at 330 nm and n-π* at 435 nm). The
effect of photoisomerization on the hydrogel structure was
investigated by microscopy. Ultraviolet (UV)
irradiation-induced reduction in hydrogel size was observed,
which may be a result of the inherently smaller footprint of
the cis azobenzene conformation, as well as dipole-dipole
interactions between the polar cis azobenzene and the
polymer network. The UV-triggered reduction in hydrogel size
was accompanied by enhanced release of the near-infrared
fluorescent dye Alexa Fluor 750 (AF<sub>750</sub>). Enhanced
release of AF<sub>750</sub> was observed in samples
irradiated with UV versus dark control. Together, these data
demonstrate the potential of these systems as reversible
photoresponsive biomaterials.},
Doi = {10.1021/acsami.6b16183},
Key = {fds327223}
}
@article{fds335903,
Author = {Navarro, LA and French, DL and Zauscher, S},
Title = {Synthesis of Modular Brush Polymer-Protein Hybrids Using
Diazotransfer and Copper Click Chemistry.},
Journal = {Bioconjugate Chemistry},
Volume = {29},
Number = {8},
Pages = {2594-2605},
Year = {2018},
Month = {August},
url = {http://dx.doi.org/10.1021/acs.bioconjchem.8b00309},
Abstract = {Proteoglycans are important brush-like biomacromolecules,
which serve a variety of functions in the human body. While
protein-bottlebrush hybrids are promising proteoglycan
mimics, many challenges still exist to robustly produce such
polymers. In this paper, we report the modular synthesis of
protein-brush hybrids containing elastin-like polypeptides
(ELP) as model proteins by copper-catalyzed azide-alkyne
cycloaddition. We exploit the recently discovered
imidazole-1-sulfonyl azide (ISA) in a diazotransfer reaction
to introduce an N-terminal azide onto an ELP. Next, we use a
click reaction to couple the azido-ELP to an
alkyne-terminated amine-rich polymer followed by a second
diazotransfer step to produce an azide-rich backbone that
serves as a scaffold. Finally, we used a second click
reaction to graft alkyne-terminated poly(oligoethylene
glycol methacrylate) (POEGMA) bristles to the azide-rich
backbone to produce the final protein-bottlebrush hybrid. We
demonstrate the effectiveness of this synthetic path at each
step through careful characterization with <sup>1</sup>H
NMR, FTIR, GPC, and diagnostic test reactions on SDS-PAGE.
Final reaction products could be consistently obtained for a
variety of different molecular weight backbones with final
total grafting efficiencies around 70%. The high-yielding
reactions employed in this highly modular approach allow for
the synthesis of protein-bottlebrush hybrids with different
proteins and brush polymers. Additionally, the mild reaction
conditions used have the potential to avoid damage to
proteins during synthesis.},
Doi = {10.1021/acs.bioconjchem.8b00309},
Key = {fds335903}
}
@article{fds335904,
Author = {Gu, R and Oweida, T and Yingling, YG and Chilkoti, A and Zauscher,
S},
Title = {Enzymatic Synthesis of Nucleobase-Modified Single-Stranded
DNA Offers Tunable Resistance to Nuclease
Degradation.},
Journal = {Biomacromolecules},
Volume = {19},
Number = {8},
Pages = {3525-3535},
Publisher = {American Chemical Society (ACS)},
Year = {2018},
Month = {August},
url = {http://dx.doi.org/10.1021/acs.biomac.8b00816},
Abstract = {We synthesized long, nucleobase-modified, single-stranded
DNA (ssDNA) using terminal deoxynucleotidyl transferase
(TdT) enzymatic polymerization. Specifically, we
investigated the effect of unnatural nucleobase size and
incorporation density on ssDNA resistance to exo- and
endonuclease degradation. We discovered that increasing the
size and density of unnatural nucleobases enhances ssDNA
resistance to degradation in the presence of exonuclease I,
DNase I, and human serum. We also studied the mechanism of
this resistance enhancement using molecular dynamics
simulations. Our results show that the presence of unnatural
nucleobases in ssDNA decreases local chain flexibility and
hampers nuclease access to the ssDNA backbone, which hinders
nuclease binding to ssDNA and slows its degradation. Our
discoveries suggest that incorporating nucleobase-modified
nucleotides into ssDNA, using enzymatic polymerization, is
an easy and efficient strategy to prolong and tune the
half-life of DNA-based materials in nucleases-containing
environments.},
Doi = {10.1021/acs.biomac.8b00816},
Key = {fds335904}
}
@article{fds335905,
Author = {Maskarinec, SA and Parlak, Z and Tu, Q and Levering, V and Zauscher, S and López, GP and Fowler, VG and Perfect, JR},
Title = {On-demand release of Candida albicans biofilms from urinary
catheters by mechanical surface deformation.},
Journal = {Biofouling},
Volume = {34},
Number = {6},
Pages = {595-604},
Year = {2018},
Month = {July},
url = {http://dx.doi.org/10.1080/08927014.2018.1474461},
Abstract = {Candida albicans is a leading cause of catheter-associated
urinary tract infections and elimination of these
biofilm-based infections without antifungal agents would
constitute a significant medical advance. A novel urinary
catheter prototype that utilizes on-demand surface
deformation is effective at eliminating bacterial biofilms
and here the broader applicability of this prototype to
remove fungal biofilms has been demonstrated. C. albicans
biofilms were debonded from prototypes by selectively
inflating four additional intralumens surrounding the main
lumen of the catheters to provide the necessary surface
strain to remove the adhered biofilm. Deformable catheters
eliminated significantly more biofilm than the controls
(>90% eliminated vs 10% control; p < 0.001). Mechanical
testing revealed that fungal biofilms have an elastic
modulus of 45 ± 6.7 kPa with a fracture energy of
0.4-2 J m-2. This study underscores the potential of
mechanical disruption as a materials design strategy to
combat fungal device-associated infections.},
Doi = {10.1080/08927014.2018.1474461},
Key = {fds335905}
}
@article{fds333788,
Author = {Shields, CW and White, JP and Osta, EG and Patel, J and Rajkumar, S and Kirby, N and Therrien, J-P and Zauscher, S},
Title = {Encapsulation and controlled release of retinol from
silicone particles for topical delivery.},
Journal = {Journal of Controlled Release : Official Journal of the
Controlled Release Society},
Volume = {278},
Pages = {37-48},
Year = {2018},
Month = {May},
url = {http://dx.doi.org/10.1016/j.jconrel.2018.03.023},
Abstract = {Retinol, a derivative of vitamin A, is a ubiquitous compound
used to treat acne, reduce wrinkles and protect against
conditions like psoriasis and ichthyosis. While retinol is
used as the primary active ingredient (AI) in many skin care
formulations, its efficacy is often limited by an extreme
sensitivity to degrade and toxicity at high concentrations.
While microencapsulation is an appealing method to help
overcome these issues, few microencapsulation strategies
have made a major translational impact due to challenges
with complexity, cost, limited protection of the AI and poor
control of the release of the AI. We have developed a class
of silicone particles that addresses these challenges for
the encapsulation, protection and controlled release of
retinol and other hydrophobic compounds. The particles are
prepared by the sol-gel polymerization of silane monomers,
which enables their rapid and facile synthesis at scale
while maintaining a narrow size distribution (i.e.,
CV < 20%). We show that our particles can: (i)
encapsulate retinol with high efficiency (>85%), (ii)
protect retinol from degradation (yielding a half-life 9×
greater than unencapsulated retinol) and (iii) slowly
release retinol over several hours (at rates from 0.14 to
0.67 μg cm-2 s-1/2). To demonstrate that the
controlled release of retinol from the particles can reduce
irritation, we performed a double blind study on human
subjects and found that formulations containing our
particles were 12-23% less irritating than identical
formulations containing Microsponge® particles (an industry
standard by Amcol, Inc.). To show that the silicone
particles can elicit a favorable biological response,
similar to the Microsponge® particles, we applied both
formulations to reconstructed human epidermal tissues and
found an upregulation of keratin 19 (K19) and a
downregulation of K10, indicating that the reduced
irritation observed in the human study was not caused by
reduced activity. We also found a decrease in the production
of interleukin-1α (IL-1α) compared to formulations
containing the Microsponge particles, suggesting lower
irritation levels and supporting the findings from the human
study. Finally, we show that the silicone particles can
encapsulate other AIs, including betamethasone, N,
N-diethyl-meta-toluamide (DEET), homosalate and ingenol
mebutate, establishing these particles as a true platform
technology.},
Doi = {10.1016/j.jconrel.2018.03.023},
Key = {fds333788}
}
@article{fds331313,
Author = {Costa, SA and Simon, JR and Amiram, M and Tang, L and Zauscher, S and Brustad, EM and Isaacs, FJ and Chilkoti, A},
Title = {Photo-Crosslinkable Unnatural Amino Acids Enable Facile
Synthesis of Thermoresponsive Nano- to Microgels of
Intrinsically Disordered Polypeptides.},
Journal = {Advanced Materials (Deerfield Beach, Fla.)},
Volume = {30},
Number = {5},
Year = {2018},
Month = {February},
url = {http://dx.doi.org/10.1002/adma.201704878},
Abstract = {Hydrogel particles are versatile materials that provide
exquisite, tunable control over the sequestration and
delivery of materials in pharmaceutics, tissue engineering,
and photonics. The favorable properties of hydrogel
particles depend largely on their size, and particles
ranging from nanometers to micrometers are used in different
applications. Previous studies have only successfully
fabricated these particles in one specific size regime and
required a variety of materials and fabrication methods. A
simple yet powerful system is developed to easily tune the
size of polypeptide-based, thermoresponsive hydrogel
particles, from the nano- to microscale, using a single
starting material. Particle size is controlled by the
self-assembly and unique phase transition behavior of
elastin-like polypeptides in bulk and within
microfluidic-generated droplets. These particles are then
stabilized through ultraviolet irradiation of a
photo-crosslinkable unnatural amino acid (UAA)
cotranslationally incorporated into the parent polypeptide.
The thermoresponsive property of these particles provides an
active mechanism for actuation and a dynamic responsive to
the environment. This work represents a fundamental advance
in the generation of crosslinked biomaterials, especially in
the form of soft matter colloids, and is one of the first
demonstrations of successful use of UAAs in generating a
novel material.},
Doi = {10.1002/adma.201704878},
Key = {fds331313}
}
@article{fds333231,
Author = {Marusak, KE and Krug, JR and Feng, Y and Cao, Y and You, L and Zauscher,
S},
Title = {Bacterially driven cadmium sulfide precipitation on porous
membranes: Toward platforms for photocatalytic
applications.},
Journal = {Biointerphases},
Volume = {13},
Number = {1},
Pages = {011006},
Year = {2018},
Month = {February},
url = {http://dx.doi.org/10.1116/1.5008393},
Abstract = {The emerging field of biofabrication capitalizes on nature's
ability to create materials with a wide range of
well-defined physical and electronic properties.
Particularly, there is a current push to utilize programmed,
self-organization of living cells for material fabrication.
However, much research is still necessary at the interface
of synthetic biology and materials engineering to make
biofabrication a viable technique to develop functional
devices. Here, the authors exploit the ability of
Escherichia coli to contribute to material fabrication by
designing and optimizing growth platforms to direct
inorganic nanoparticle (NP) synthesis, specifically cadmium
sulfide (CdS) NPs, onto porous polycarbonate membranes.
Additionally, current, nonbiological, chemical synthesis
methods for CdS NPs are typically energy intensive and use
high concentrations of hazardous cadmium precursors. Using
biosynthesis methods through microorganisms could
potentially alleviate these issues by precipitating NPs with
less energy and lower concentrations of toxic precursors.
The authors adopted extracellular precipitation strategies
to form CdS NPs on the membranes as bacterial/membrane
composites and characterized them by spectroscopic and
imaging methods, including energy dispersive spectroscopy,
and scanning and transmission electron microscopy. This
method allowed us to control the localization of NP
precipitation throughout the layered bacterial/membrane
composite, by varying the timing of the cadmium precursor
addition. Additionally, the authors demonstrated the
photodegradation of methyl orange using the CdS
functionalized porous membranes, thus confirming the
photocatalytic properties of these composites for eventual
translation to device development. If combined with the
genetically programmed self-organization of cells, this
approach promises to directly pattern CdS nanostructures on
solid supports.},
Doi = {10.1116/1.5008393},
Key = {fds333231}
}
@article{fds332900,
Author = {Li, L and Li, NK and Tu, Q and Im, O and Mo, C-K and Han, W and Fuss, WH and Carroll, NJ and Chilkoti, A and Yingling, YG and Zauscher, S and López,
GP},
Title = {Functional Modification of Silica through Enhanced
Adsorption of Elastin-Like Polypeptide Block
Copolymers.},
Journal = {Biomacromolecules},
Volume = {19},
Number = {2},
Pages = {298-306},
Year = {2018},
Month = {February},
url = {http://dx.doi.org/10.1021/acs.biomac.7b01307},
Abstract = {A powerful tool for controlling interfacial properties and
molecular architecture relies on the tailored adsorption of
stimuli-responsive block copolymers onto surfaces. Here, we
use computational and experimental approaches to investigate
the adsorption behavior of thermally responsive polypeptide
block copolymers (elastin-like polypeptides, ELPs) onto
silica surfaces, and to explore the effects of surface
affinity and micellization on the adsorption kinetics and
the resultant polypeptide layers. We demonstrate that
genetic incorporation of a silica-binding peptide (silaffin
R5) results in enhanced adsorption of these block copolymers
onto silica surfaces as measured by quartz crystal
microbalance and ellipsometry. We find that the silaffin
peptide can also direct micelle adsorption, leading to
close-packed micellar arrangements that are distinct from
the sparse, patchy arrangements observed for ELP micelles
lacking a silaffin tag, as evidenced by atomic force
microscopy measurements. These experimental findings are
consistent with results of dissipative particle dynamics
simulations. Wettability measurements suggest that surface
immobilization hampers the temperature-dependent
conformational change of ELP micelles, while adsorbed ELP
unimers (i.e., unmicellized block copolymers) retain their
thermally responsive property at interfaces. These
observations provide guidance on the use of ELP block
copolymers as building blocks for fabricating smart surfaces
and interfaces with programmable architecture and
functionality.},
Doi = {10.1021/acs.biomac.7b01307},
Key = {fds332900}
}
@article{fds339853,
Author = {Yildiz, T and Gu, R and Zauscher, S and Betancourt,
T},
Title = {Doxorubicin-loaded protease-activated near-infrared
fluorescent polymeric nanoparticles for imaging and therapy
of cancer.},
Journal = {International Journal of Nanomedicine},
Volume = {13},
Pages = {6961-6986},
Year = {2018},
Month = {January},
url = {http://dx.doi.org/10.2147/ijn.s174068},
Abstract = {<h4>Introduction</h4>Despite significant progress in the
field of oncology, cancer remains one of the leading causes
of death. Chemotherapy is one of the most common treatment
options for cancer patients but is well known to result in
off-target toxicity. Theranostic nanomedicines that
integrate diagnostic and therapeutic functions within an
all-in-one platform can increase tumor selectivity for more
effective chemotherapy and aid in diagnosis and monitoring
of therapeutic responses.<h4>Material and methods</h4>In
this work, theranostic nanoparticles were synthesized with
commonly used biocompatible and biodegradable polymers and
used as cancer contrast and therapeutic agents for optical
imaging and treatment of breast cancer. These core-shell
nanoparticles were prepared by nanoprecipitation of blends
of the biodegradable and biocompatible amphiphilic
copolymers poly(lactic-<i>co</i>-glycolic
acid)-<i>b</i>-poly-l-lysine and poly(lactic
acid)-<i>b</i>-poly(ethylene glycol). Poly-l-lysine in the
first copolymer was covalently decorated with near-infrared
fluorescent Alexa Fluor 750 molecules.<h4>Results</h4>The
spherical nanoparticles had an average size of 60-80 nm. The
chemotherapeutic drug doxorubicin was encapsulated in the
core of nanoparticles at a loading of 3% (w:w) and
controllably released over a period of 30 days. A 33-fold
increase in near-infrared fluorescence, mediated by
protease-mediated cleavage of the Alexa Fluor 750-labeled
poly-l-lysine on the surface of the nanoparticles, was
observed upon interaction with the model protease trypsin.
The cytocompatibility of drug-free nanoparticles and growth
inhibition of drug-loaded nanoparticles on MDA-MB-231 breast
cancer cells were investigated with a luminescence
cell-viability assay. Drug-free nanoparticles were found to
cause minimal toxicity, even at high concentrations
(0.2-2,000 µg/mL), while doxorubicin-loaded nanoparticles
significantly reduced cell viability at drug concentrations
>10 µM. Finally, the interaction of the nanoparticles with
breast cancer cells was studied utilizing fluorescence
microscopy, demonstrating the potential of the nanoparticles
to act as near-infrared fluorescence optical imaging agents
and drug-delivery carriers.<h4>Conclusion</h4>Doxorubicin-loaded,
enzymatically activatable nanoparticles of less than 100 nm
were prepared successfully by nanoprecipitation of copolymer
blends. These nanoparticles were found to be suitable as
controlled drug delivery systems and contrast agents for
imaging of cancer cells.},
Doi = {10.2147/ijn.s174068},
Key = {fds339853}
}
@article{fds357336,
Author = {Maniura-Weber, K and Zauscher, S and McArthur,
S},
Title = {Some changes, but still communicating exciting key insights
from the biointerface.},
Journal = {Biointerphases},
Volume = {12},
Number = {5},
Pages = {050201},
Year = {2018},
Month = {January},
url = {http://dx.doi.org/10.1116/1.5018515},
Doi = {10.1116/1.5018515},
Key = {fds357336}
}
@article{fds330454,
Author = {Cao, Y and Feng, Y and Ryser, MD and Zhu, K and Herschlag, G and Cao, C and Marusak, K and Zauscher, S and You, L},
Title = {Programmable assembly of pressure sensors using
pattern-forming bacteria.},
Journal = {Nat Biotechnol},
Volume = {35},
Number = {11},
Pages = {1087-1093},
Year = {2017},
Month = {November},
url = {http://dx.doi.org/10.1038/nbt.3978},
Abstract = {Biological systems can generate microstructured materials
that combine organic and inorganic components and possess
diverse physical and chemical properties. However, these
natural processes in materials fabrication are not readily
programmable. Here, we use a synthetic-biology approach to
assemble patterned materials. We demonstrate programmable
fabrication of three-dimensional (3D) materials by printing
engineered self-patterning bacteria on permeable membranes
that serve as a structural scaffold. Application of gold
nanoparticles to the colonies creates hybrid
organic-inorganic dome structures. The dynamics of the dome
structures' response to pressure is determined by their
geometry (colony size, dome height, and pattern), which is
easily modified by varying the properties of the membrane
(e.g., pore size and hydrophobicity). We generate resettable
pressure sensors that process signals in response to varying
pressure intensity and duration.},
Doi = {10.1038/nbt.3978},
Key = {fds330454}
}
@article{fds329514,
Author = {Li, NK and Kuang, H and Fuss, WH and Zauscher, S and Kokkoli, E and Yingling, YG},
Title = {Salt Responsive Morphologies of ssDNA-Based Triblock
Polyelectrolytes in Semi-Dilute Regime: Effect of Volume
Fractions and Polyelectrolyte Length.},
Journal = {Macromolecular Rapid Communications},
Volume = {38},
Number = {20},
Year = {2017},
Month = {October},
url = {http://dx.doi.org/10.1002/marc.201700422},
Abstract = {A comprehensive study is reported on the effect of salt
concentration, polyelectrolyte block length, and polymer
concentration on the morphology and structural properties of
nanoaggregates self-assembled from BAB single-strand DNA
(ssDNA) triblock polynucleotides in which A represents
polyelectrolyte blocks and B represents hydrophobic neutral
blocks. A morphological phase diagram above the gelation
point is developed as a function of solvent ionic strength
and polyelectrolyte block length utilizing an implicit
solvent ionic strength method for dissipative particle
dynamics simulations. As the solvent ionic strength
increases, the self-assembled DNA network structures shrinks
considerably, leading to a morphological transition from a
micellar network to worm-like or hamburger-shape aggregates.
This study provides insight into the network morphology and
its changes by calculating the aggregation number, number of
hydrophobic cores, and percentage of bridge chains in the
network. The simulation results are corroborated through
cryogenic transmission electron microscopy on the example of
the self-assembly of ssDNA triblocks.},
Doi = {10.1002/marc.201700422},
Key = {fds329514}
}
@article{fds328288,
Author = {Du, K-Z and Tu, Q and Zhang, X and Han, Q and Liu, J and Zauscher, S and Mitzi, DB},
Title = {Two-Dimensional Lead(II) Halide-Based Hybrid Perovskites
Templated by Acene Alkylamines: Crystal Structures, Optical
Properties, and Piezoelectricity.},
Journal = {Inorganic Chemistry},
Volume = {56},
Number = {15},
Pages = {9291-9302},
Year = {2017},
Month = {August},
url = {http://dx.doi.org/10.1021/acs.inorgchem.7b01094},
Abstract = {A series of two-dimensional (2D) hybrid organic-inorganic
perovskite (HOIP) crystals, based on acene alkylamine
cations (i.e., phenylmethylammonium (PMA),
2-phenylethylammonium (PEA), 1-(2-naphthyl)methanammonium
(NMA), and 2-(2-naphthyl)ethanammonium (NEA)) and lead(II)
halide (i.e., PbX<sub>4</sub><sup>2-</sup>, X = Cl, Br, and
I) frameworks, and their corresponding thin films were
fabricated and examined for structure-property relationship.
Several new or redetermined crystal structures are reported,
including those for (NEA)<sub>2</sub>PbI<sub>4</sub>,
(NEA)<sub>2</sub>PbBr<sub>4</sub>, (NMA)<sub>2</sub>PbBr<sub>4</sub>,
(PMA)<sub>2</sub>PbBr<sub>4</sub>, and (PEA)<sub>2</sub>PbI<sub>4</sub>.
Non-centrosymmetric structures from among these 2D HOIPs
were confirmed by piezoresponse force microscopy-especially
noteworthy is the structure of (PMA)<sub>2</sub>PbBr<sub>4</sub>,
which was previously reported as centrosymmetric.
Examination of the impact of organic cation and inorganic
layer choice on the exciton absorption/emission properties,
among the set of compounds considered, reveals that
perovskite layer distortion (i.e., Pb-I-Pb bond angle
between adjacent PbI<sub>6</sub> octahedra) has a more
global effect on the exciton properties than octahedral
distortion (i.e., variation of I-Pb-I bond angles and
discrepancy among Pb-I bond lengths within each
PbI<sub>6</sub> octahedron). In addition to the
characteristic sharp exciton emission for each perovskite,
(PMA)<sub>2</sub>PbCl<sub>4</sub>, (PEA)<sub>2</sub>PbCl<sub>4</sub>,
(NMA)<sub>2</sub>PbCl<sub>4</sub>, and (PMA)<sub>2</sub>PbBr<sub>4</sub>
exhibit separate, broad "white" emission in the long
wavelength range. Piezoelectric compounds identified from
these 2D HOIPs may be considered for future
piezoresponse-type energy or electronic applications.},
Doi = {10.1021/acs.inorgchem.7b01094},
Key = {fds328288}
}
@article{fds326497,
Author = {Tang, L and Navarro, LA and Chilkoti, A and Zauscher,
S},
Title = {High-Molecular-Weight Polynucleotides by
Transferase-Catalyzed Living Chain-Growth
Polycondensation.},
Journal = {Angewandte Chemie International Edition},
Volume = {56},
Number = {24},
Pages = {6778-6782},
Publisher = {WILEY},
Year = {2017},
Month = {June},
url = {http://dx.doi.org/10.1002/anie.201700991},
Abstract = {We present terminal deoxynucleotidyl transferase-catalyzed
enzymatic polymerization (TcEP) for the template-free
synthesis of high-molecular-weight, single-stranded DNA
(ssDNA) and demonstrate that it proceeds by a living
chain-growth polycondensation mechanism. We show that the
molecular weight of the reaction products is nearly
monodisperse, and can be manipulated by the feed ratio of
nucleotide (monomer) to oligonucleotide (initiator), as
typically observed for living polymerization reactions.
Understanding the synthesis mechanism and the reaction
kinetics enables the rational, template-free synthesis of
ssDNA that can be used for a range of biomedical and
nanotechnology applications.},
Doi = {10.1002/anie.201700991},
Key = {fds326497}
}
@article{fds325857,
Author = {Tu, Q and Kim, HS and Oweida, TJ and Parlak, Z and Yingling, YG and Zauscher, S},
Title = {Interfacial Mechanical Properties of Graphene on
Self-Assembled Monolayers: Experiments and
Simulations.},
Journal = {Acs Applied Materials & Interfaces},
Volume = {9},
Number = {11},
Pages = {10203-10213},
Year = {2017},
Month = {March},
url = {http://dx.doi.org/10.1021/acsami.6b16593},
Abstract = {Self-assembled monolayers (SAMs) have been widely used to
engineer the electronic properties of substrate-supported
graphene devices. However, little is known about how the
surface chemistry of SAMs affects the interfacial mechanical
properties of graphene supported on SAMs. Fluctuations and
changes in these properties affect the stress transfer
between substrate and the supported graphene and thus the
performance of graphene-based devices. The changes in
interfacial mechanical properties can be characterized by
measuring the out-of-plane elastic properties. Combining
contact resonance atomic force microcopy experiments with
molecular dynamics simulations, we show that the head group
chemistry of a SAM, which affects the interfacial
interactions, can have a significant effect on the
out-of-plane elastic modulus of the graphene-SAM
heterostructure. Graphene supported on hydrophobic SAMs
leads to heterostructures stiffer than those of graphene
supported on hydrophilic SAMs, which is largely due to fewer
water molecules present at the graphene-SAM interface. Our
results provide an important, and often overlooked, insight
into the mechanical properties of substrate-supported
graphene electronics.},
Doi = {10.1021/acsami.6b16593},
Key = {fds325857}
}
@article{fds325392,
Author = {Feng, Y and Ngaboyamahina, E and Marusak, KE and Cao, Y and You, L and Glass, JT and Zauscher, S},
Title = {Hybrid (Organic/Inorganic) Electrodes from Bacterially
Precipitated CdS for PEC/Storage Applications},
Journal = {The Journal of Physical Chemistry C},
Volume = {121},
Number = {7},
Pages = {3734-3743},
Publisher = {American Chemical Society (ACS)},
Year = {2017},
Month = {February},
url = {http://dx.doi.org/10.1021/acs.jpcc.6b11387},
Abstract = {Hybrid organic-inorganic compounds are receiving increasing
attention for photoelectrochemical (PEC) devices due to
their high electron transport efficiency and facile
synthesis. Biosynthesis is a potentially low-cost and
eco-friendly method to precipitate transition-metal-based
semiconductor nanoparticles (NPs) in an organic matrix. In
this work, we examine the structure and composition of
bacterially precipitated (BAC) cadmium sulfide (CdS) NPs
using electron microscopy, and we determine their PEC
properties and the energy band structure by electrochemical
measurements. In addition, by taking advantage of the
organic matrix, which is residual from the biosynthesis
process, we fabricate a prototype photocharged capacitor
electrode by incorporating the bacterially precipitated CdS
with a reduced graphene oxide (RGO) sheet. Our results show
that the hydrophilic groups associated with the organic
matrix make BAC CdS NPs a potentially useful component of
PEC devices with applications for energy conversion and
storage. (Graph Presented).},
Doi = {10.1021/acs.jpcc.6b11387},
Key = {fds325392}
}
@article{fds319122,
Author = {Tu, Q and Lange, B and Parlak, Z and Lopes, JMJ and Blum, V and Zauscher,
S},
Title = {Quantitative Subsurface Atomic Structure Fingerprint for 2D
Materials and Heterostructures by First-Principles-Calibrated
Contact-Resonance Atomic Force Microscopy.},
Journal = {Acs Nano},
Volume = {10},
Number = {7},
Pages = {6491-6500},
Year = {2016},
Month = {July},
url = {http://dx.doi.org/10.1021/acsnano.6b02402},
Abstract = {Interfaces and subsurface layers are critical for the
performance of devices made of 2D materials and
heterostructures. Facile, nondestructive, and quantitative
ways to characterize the structure of atomically thin,
layered materials are thus essential to ensure control of
the resultant properties. Here, we show that
contact-resonance atomic force microscopy-which is
exquisitely sensitive to stiffness changes that arise from
even a single atomic layer of a van der Waals-adhered
material-is a powerful experimental tool to address this
challenge. A combined density functional theory and
continuum modeling approach is introduced that yields
sub-surface-sensitive, nanomechanical fingerprints
associated with specific, well-defined structure models of
individual surface domains. Where such models are known,
this information can be correlated with experimentally
obtained contact-resonance frequency maps to reveal the
(sub)surface structure of different domains on the
sample.},
Doi = {10.1021/acsnano.6b02402},
Key = {fds319122}
}
@article{fds319125,
Author = {Marusak, KE and Feng, Y and Eben, CF and Payne, ST and Cao, Y and You, L and Zauscher, S},
Title = {Cadmium sulphide quantum dots with tunable electronic
properties by bacterial precipitation.},
Journal = {Rsc Adv.},
Volume = {6},
Number = {80},
Pages = {76158-76166},
Year = {2016},
Month = {January},
url = {http://dx.doi.org/10.1039/c6ra13835g},
Abstract = {We present a new method to fabricate semiconducting,
transition metal nanoparticles (NPs) with tunable bandgap
energies using engineered <i>Escherichia coli</i>. These
bacteria overexpress the <i>Treponema denticola</i> cysteine
desulfhydrase gene to facilitate precipitation of cadmium
sulphide (CdS) NPs. Analysis with transmission electron
microscopy, X-ray diffraction, and X-ray photoelectron
spectroscopy reveal that the bacterially precipitated NPs
are agglomerates of mostly quantum dots, with diameters that
can range from 3 to 15 nm, embedded in a carbon-rich matrix.
Additionally, conditions for bacterial CdS precipitation can
be tuned to produce NPs with bandgap energies that range
from quantum-confined to bulk CdS. Furthermore, inducing
precipitation at different stages of bacterial growth allows
for control over whether the precipitation occurs intra- or
extracellularly. This control can be critically important in
utilizing bacterial precipitation for the
environmentally-friendly fabrication of functional,
electronic and catalytic materials. Notably, the measured
photoelectrochemical current generated by these NPs is
comparable to values reported in the literature and higher
than that of synthesized chemical bath deposited CdS NPs.
This suggests that bacterially precipitated CdS NPs have
potential for applications ranging from photovoltaics to
photocatalysis in hydrogen evolution.},
Doi = {10.1039/c6ra13835g},
Key = {fds319125}
}
@article{fds319123,
Author = {Yu, Q and Ista, LK and Gu, R and Zauscher, S and López,
GP},
Title = {Nanopatterned polymer brushes: conformation, fabrication and
applications.},
Journal = {Nanoscale},
Volume = {8},
Number = {2},
Pages = {680-700},
Year = {2016},
Month = {January},
url = {http://dx.doi.org/10.1039/c5nr07107k},
Abstract = {Surfaces with end-grafted, nanopatterned polymer brushes
that exhibit well-defined feature dimensions and controlled
chemical and physical properties provide versatile platforms
not only for investigation of nanoscale phenomena at
biointerfaces, but also for the development of advanced
devices relevant to biotechnology and electronics
applications. In this review, we first give a brief
introduction of scaling behavior of nanopatterned polymer
brushes and then summarize recent progress in fabrication
and application of nanopatterned polymer brushes.
Specifically, we highlight applications of nanopatterned
stimuli-responsive polymer brushes in the areas of
biomedicine and biotechnology.},
Doi = {10.1039/c5nr07107k},
Key = {fds319123}
}
@article{fds319124,
Author = {Tkatchenko, AV and Luo, X and Tkatchenko, TV and Vaz, C and Tanavde, VM and Maurer-Stroh, S and Zauscher, S and Gonzalez, P and Young,
TL},
Title = {Large-Scale microRNA Expression Profiling Identifies
Putative Retinal miRNA-mRNA Signaling Pathways Underlying
Form-Deprivation Myopia in Mice.},
Journal = {Plos One},
Volume = {11},
Number = {9},
Pages = {e0162541},
Year = {2016},
url = {http://dx.doi.org/10.1371/journal.pone.0162541},
Abstract = {Development of myopia is associated with large-scale changes
in ocular tissue gene expression. Although differential
expression of coding genes underlying development of myopia
has been a subject of intense investigation, the role of
non-coding genes such as microRNAs in the development of
myopia is largely unknown. In this study, we explored
myopia-associated miRNA expression profiles in the retina
and sclera of C57Bl/6J mice with experimentally induced
myopia using microarray technology. We found a total of 53
differentially expressed miRNAs in the retina and no
differences in miRNA expression in the sclera of C57BL/6J
mice after 10 days of visual form deprivation, which induced
-6.93 ± 2.44 D (p < 0.000001, n = 12) of myopia. We also
identified their putative mRNA targets among mRNAs found to
be differentially expressed in myopic retina and potential
signaling pathways involved in the development of
form-deprivation myopia using miRNA-mRNA interaction network
analysis. Analysis of myopia-associated signaling pathways
revealed that myopic response to visual form deprivation in
the retina is regulated by a small number of highly
integrated signaling pathways. Our findings highlighted that
changes in microRNA expression are involved in the
regulation of refractive eye development and predicted how
they may be involved in the development of myopia by
regulating retinal gene expression.},
Doi = {10.1371/journal.pone.0162541},
Key = {fds319124}
}
@article{fds263324,
Author = {Gu, R and Lamas, J and Rastogi, SK and Li, X and Brittain, W and Zauscher,
S},
Title = {Photocontrolled micellar aggregation of amphiphilic
DNA-azobenzene conjugates.},
Journal = {Colloids and Surfaces. B, Biointerfaces},
Volume = {135},
Pages = {126-132},
Year = {2015},
Month = {November},
ISSN = {0927-7765},
url = {http://dx.doi.org/10.1016/j.colsurfb.2015.07.010},
Abstract = {We demonstrate the reversible micellar aggregation of a
DNA-azobenzene conjugate in aqueous conditions, in which the
photoisomerization of the initially apolar trans-azobenzene
moiety to the polar cis isomer causes disassembly of the
aggregates. The molecular basis for this phenomena is a
change in the hydrophobic/hydrophilic balance of the
conjugate as the more polar cis azobenzene isomer is formed
upon exposure to 365 nm irradiation. The conjugates were
prepared by copper-free Click chemistry between an
azide-modified, 53-base ssDNA and a cyclooctyne derivative
of azobenzene. The photocontrolled aggregation of the
conjugate was studied by dynamic light scattering and atomic
force microscopy. The reversible micellar aggregation for a
DNA-azobenzene conjugate has not been previously reported
and holds promise for photocontrolled drug delivery
applications.},
Doi = {10.1016/j.colsurfb.2015.07.010},
Key = {fds263324}
}
@article{fds319126,
Author = {Li, NK and Fuss, WH and Tang, L and Gu, R and Chilkoti, A and Zauscher, S and Yingling, YG},
Title = {Prediction of solvent-induced morphological changes of
polyelectrolyte diblock copolymer micelles.},
Journal = {Soft Matter},
Volume = {11},
Number = {42},
Pages = {8236-8245},
Year = {2015},
Month = {November},
url = {http://dx.doi.org/10.1039/c5sm01742d},
Abstract = {Self-assembly processes of polyelectrolyte block copolymers
are ubiquitous in industrial and biological processes;
understanding their physical properties can also provide
insights into the design of polyelectrolyte materials with
novel and tailored properties. Here, we report systematic
analysis on how the ionic strength of the solvent and the
length of the polyelectrolyte block affect the self-assembly
and morphology of the polyelectrolyte block copolymer
materials by constructing a salt-dependent morphological
phase diagram using an implicit solvent ionic strength
(ISIS) method for dissipative particle dynamics (DPD)
simulations. This diagram permits the determination of the
conditions for the morphological transition into a specific
shape, namely vesicles or lamellar aggregates,
wormlike/cylindrical micelles, and spherical micelles. The
scaling behavior for the size of spherical micelles is
predicted, in terms of radius of gyration (R(g,m)) and
thickness of corona (Hcorona), as a function of solvent
ionic strength (c(s)) and polyelectrolyte length (NA), which
are R(g,m) ∼ c(s)(-0.06)N(A)(0.54) and Hcorona ∼
c(s)(-0.11)N(A)(0.75). The simulation results were
corroborated through AFM and static light scattering
measurements on the example of the self-assembly of
monodisperse, single-stranded DNA block-copolynucleotides
(polyT50-b-F-dUTP). Overall, we were able to predict the
salt-responsive morphology of polyelectrolyte materials in
aqueous solution and show that a spherical-cylindrical-lamellar
change in morphology can be obtained through an increase in
solvent ionic strength or a decrease of polyelectrolyte
length.},
Doi = {10.1039/c5sm01742d},
Key = {fds319126}
}
@article{fds263325,
Author = {Lee, W and Leddy, HA and Chen, Y and Lee, SH and Zelenski, NA and McNulty,
AL and Wu, J and Beicker, KN and Coles, J and Zauscher, S and Grandl, J and Sachs, F and Guilak, F and Liedtke, WB},
Title = {Synergy between Piezo1 and Piezo2 channels confers
high-strain mechanosensitivity to articular
cartilage.},
Journal = {Proc Natl Acad Sci U S A},
Volume = {111},
Number = {47},
Pages = {E5114-E5122},
Year = {2014},
Month = {November},
ISSN = {0027-8424},
url = {http://dx.doi.org/10.1073/pnas.1414298111},
Abstract = {Diarthrodial joints are essential for load bearing and
locomotion. Physiologically, articular cartilage sustains
millions of cycles of mechanical loading. Chondrocytes, the
cells in cartilage, regulate their metabolic activities in
response to mechanical loading. Pathological mechanical
stress can lead to maladaptive cellular responses and
subsequent cartilage degeneration. We sought to deconstruct
chondrocyte mechanotransduction by identifying
mechanosensitive ion channels functioning at injurious
levels of strain. We detected robust expression of the
recently identified mechanosensitive channels, PIEZO1 and
PIEZO2. Combined directed expression of Piezo1 and -2
sustained potentiated mechanically induced Ca(2+) signals
and electrical currents compared with single-Piezo
expression. In primary articular chondrocytes, mechanically
evoked Ca(2+) transients produced by atomic force microscopy
were inhibited by GsMTx4, a PIEZO-blocking peptide, and by
Piezo1- or Piezo2-specific siRNA. We complemented the
cellular approach with an explant-cartilage injury model.
GsMTx4 reduced chondrocyte death after mechanical injury,
suggesting a possible therapy for reducing cartilage injury
and posttraumatic osteoarthritis by attenuating
Piezo-mediated cartilage mechanotransduction of injurious
strains.},
Doi = {10.1073/pnas.1414298111},
Key = {fds263325}
}
@article{fds263326,
Author = {Parlak, Z and Tu, Q and Zauscher, S},
Title = {Liquid contact resonance AFM: analytical models,
experiments, and limitations.},
Journal = {Nanotechnology},
Volume = {25},
Number = {44},
Pages = {445703},
Year = {2014},
Month = {November},
ISSN = {0957-4484},
url = {http://dx.doi.org/10.1088/0957-4484/25/44/445703},
Abstract = {Contact resonance AFM (CR-AFM) is a scanning probe
microscopy technique that utilizes the contact resonances of
the AFM cantilever for concurrent imaging of topography and
surface stiffness. The technique has not been used in liquid
until recently due to analytical and experimental
difficulties, associated with viscous damping of cantilever
vibrations and fluid loading effects. To address these
difficulties, (i) an analytical approach for contact
resonances in liquid is developed, and (ii) direct
excitation of the contact resonances is demonstrated by
actuating the cantilever directly in a magnetic field. By
implementing the analytical approach and the direct
actuation through magnetic particles, quantitative stiffness
imaging on surfaces with a wide range of stiffness can be
achieved in liquid with soft cantilevers and low contact
forces.},
Doi = {10.1088/0957-4484/25/44/445703},
Key = {fds263326}
}
@article{fds263327,
Author = {Hardy, GJ and Wong, GC and Nayak, R and Anasti, K and Hirtz, M and Shapter,
JG and Alam, SM and Zauscher, S},
Title = {HIV-1 antibodies and vaccine antigen selectively interact
with lipid domains.},
Journal = {Biochimica Et Biophysica Acta},
Volume = {1838},
Number = {10},
Pages = {2662-2669},
Year = {2014},
Month = {October},
ISSN = {0006-3002},
url = {http://dx.doi.org/10.1016/j.bbamem.2014.07.007},
Abstract = {The rare, broadly neutralizing antibodies, 4E10 and 2F5,
that target the HIV-1 membrane proximal external region also
associate with HIV-1 membrane lipids as part of a required
first-step in HIV-1 neutralization. HIV-1 virions have high
concentration of cholesterol and sphingomyelin, which are
able to organize into liquid-ordered domains (i.e., lipid
rafts), and could influence the interaction of neutralizing
antibodies with epitopes proximal to the membrane. The
objective of this research is to understand how these lipid
domains contribute to 2F5/4E10 membrane interactions and to
antigen presentation in liposomal form of HIV-1 vaccines. To
this end we have engineered biomimetic supported lipid
bilayers and are able to use atomic force microscopy to
visualize membrane domains, antigen clustering, and
antibody-membrane interactions. Our results demonstrate that
2F5/4E10 do not interact with highly ordered gel and
liquid-ordered domains and exclusively bind to a
liquid-disordered lipid phase. This suggests that vaccine
liposomes that contain key viral membrane components, such
as high cholesterol content, may not be advantageous for
2F5/4E10 vaccine strategies. Rather, vaccine liposomes that
primarily contain a liquid-disordered phase may be more
likely to elicit production of lipid reactive, 2F5- and
4E10-like antibodies.},
Doi = {10.1016/j.bbamem.2014.07.007},
Key = {fds263327}
}
@article{fds263329,
Author = {Tang, L and Tjong, V and Li, N and Yingling, YG and Chilkoti, A and Zauscher, S},
Title = {Enzymatic polymerization of high molecular weight DNA
amphiphiles that self-assemble into star-like
micelles.},
Journal = {Advanced Materials (Deerfield Beach, Fla.)},
Volume = {26},
Number = {19},
Pages = {3050-3054},
Year = {2014},
Month = {May},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.201306049},
Abstract = {High molecular weight ssDNA amphiphiles are synthesized by
enzymatic polymerization. These highly asymmetric diblock
DNA copolymers self-assemble into "hairy", star-like
micelles, shown in the AFM image and the DPD
snapshot.},
Doi = {10.1002/adma.201306049},
Key = {fds263329}
}
@article{fds263331,
Author = {Tjong, V and Tang, L and Zauscher, S and Chilkoti,
A},
Title = {"Smart" DNA interfaces.},
Journal = {Chem. Soc. Rev.},
Volume = {43},
Number = {5},
Pages = {1612-1626},
Year = {2014},
Month = {March},
url = {http://www.ncbi.nlm.nih.gov/pubmed/24352168},
Abstract = {This review focuses on surface-grafted DNA, and its use as a
molecular building block that exploits its unique properties
as a directional (poly)anion that exhibits molecular
recognition. The selected examples highlight innovative
applications of DNA at surfaces and interfaces ranging from
molecular diagnostics and sequencing to biosensing.},
Doi = {10.1039/c3cs60331h},
Key = {fds263331}
}
@article{fds263330,
Author = {Chang, DP and Guilak, F and Jay, GD and Zauscher,
S},
Title = {Interaction of lubricin with type II collagen surfaces:
adsorption, friction, and normal forces.},
Journal = {Journal of Biomechanics},
Volume = {47},
Number = {3},
Pages = {659-666},
Year = {2014},
Month = {February},
url = {http://www.ncbi.nlm.nih.gov/pubmed/24406099},
Abstract = {One of the major constituents of the synovial fluid that is
thought to be responsible for chondroprotection and boundary
lubrication is the glycoprotein lubricin (PRG4); however,
the molecular mechanisms by which lubricin carries out its
critical functions still remain largely unknown. We
hypothesized that the interaction of lubricin with type II
collagen, the main component of the cartilage extracellular
matrix, results in enhanced tribological and wear
properties. In this study, we examined: (i) the molecular
details by which lubricin interacts with type II collagen
and how binding is related to boundary lubrication and
adhesive interactions; and (ii) whether collagen structure
can affect lubricin adsorption and its chondroprotective
properties. We found that lubricin adsorbs strongly onto
denatured, amorphous, and fibrillar collagen surfaces.
Furthermore, we found large repulsive interactions between
the collagen surfaces in presence of lubricin, which
increased with increasing lubricin concentration. Lubricin
attenuated the large friction and also the long-range
adhesion between fibrillar collagen surfaces. Interestingly,
lubricin adsorbed onto and mediated the frictional response
between the denatured and native amorphous collagen surfaces
equally and showed no preference on the supramolecular
architecture of collagen. However, the coefficient of
friction was lowest on fibrillar collagen in the presence of
lubricin. We speculate that an important role of lubricin in
mediating interactions at the cartilage surface is to attach
to the cartilage surface and provide a protective coating
that maintains the contacting surfaces in a sterically
repulsive state.},
Doi = {10.1016/j.jbiomech.2013.11.048},
Key = {fds263330}
}
@article{fds263337,
Author = {Wilusz, RE and Zauscher, S and Guilak, F},
Title = {Micromechanical mapping of early osteoarthritic changes in
the pericellular matrix of human articular
cartilage.},
Journal = {Osteoarthritis and Cartilage},
Volume = {21},
Number = {12},
Pages = {1895-1903},
Year = {2013},
Month = {December},
url = {http://www.ncbi.nlm.nih.gov/pubmed/24025318},
Abstract = {<h4>Objective</h4>Osteoarthritis (OA) is a degenerative
joint disease characterized by the progressive loss of
articular cartilage. While macroscale degradation of the
cartilage extracellular matrix (ECM) has been extensively
studied, microscale changes in the chondrocyte pericellular
matrix (PCM) and immediate microenvironment with OA are not
fully understood. The objective of this study was to
quantify osteoarthritic changes in the micromechanical
properties of the ECM and PCM of human articular cartilage
in situ using atomic force microscopy (AFM).<h4>Method</h4>AFM
elastic mapping was performed on cryosections of human
cartilage harvested from both condyles of macroscopically
normal and osteoarthritic knee joints. This method was used
to test the hypotheses that both ECM and PCM regions exhibit
a loss of mechanical properties with OA and that the size of
the PCM is enlarged in OA cartilage as compared to normal
tissue.<h4>Results</h4>Significant decreases were observed
in both ECM and PCM moduli of 45% and 30%, respectively, on
the medial condyle of OA knee joints as compared to
cartilage from macroscopically normal joints. Enlargement of
the PCM, as measured biomechanically, was also observed in
medial condyle OA cartilage, reflecting the underlying
distribution of type VI collagen in the region. No
significant differences were observed in elastic moduli or
their spatial distribution on the lateral condyle between
normal and OA joints.<h4>Conclusion</h4>Our findings provide
new evidence of significant site-specific degenerative
changes in the chondrocyte micromechanical environment with
OA.},
Doi = {10.1016/j.joca.2013.08.026},
Key = {fds263337}
}
@article{fds263338,
Author = {Malmsten, M and Zauscher, S},
Title = {Colloids and surfaces in biology},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {18},
Number = {5},
Pages = {379-380},
Publisher = {Elsevier BV},
Year = {2013},
Month = {October},
ISSN = {1359-0294},
url = {http://dx.doi.org/10.1016/j.cocis.2013.07.003},
Doi = {10.1016/j.cocis.2013.07.003},
Key = {fds263338}
}
@article{fds263340,
Author = {Hardy, GJ and Nayak, R and Zauscher, S},
Title = {Model cell membranes: Techniques to form complex biomimetic
supported lipid bilayers via vesicle fusion.},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {18},
Number = {5},
Pages = {448-458},
Year = {2013},
Month = {October},
ISSN = {1359-0294},
url = {http://dx.doi.org/10.1016/j.cocis.2013.06.004},
Abstract = {Vesicle fusion has long provided an easy and reliable method
to form supported lipid bilayers (SLBs) from simple,
zwitterionic vesicles on siliceous substrates. However, for
complex compositions, such as vesicles with high cholesterol
content and multiple lipid types, the energy barrier for the
vesicle-to-bilayer transition is increased or the required
vesicle-vesicle and vesicle-substrate interactions are
insufficient for vesicle fusion. Thus, for vesicle
compositions that more accurately mimic native membranes,
vesicle fusion often fails to form SLBs. In this paper, we
review three approaches to overcome these barriers to form
complex, biomimetic SLBs via vesicle fusion: (i)
optimization of experimental conditions (e.g., temperature,
buffer ionic strength, osmotic stress, cation valency, and
buffer pH), (ii) α-helical (AH) peptide-induced vesicle
fusion, and (iii) bilayer edge-induced vesicle fusion. AH
peptide-induced vesicle fusion can form complex SLBs on
multiple substrate types without the use of additional
equipment. Bilayer edge-induced vesicle fusion uses
microfluidics to form SLBs from vesicles with complex
composition, including vesicles derived from native cell
membranes. Collectively, this review introduces vesicle
fusion techniques that can be generalized for many
biomimetic vesicle compositions and many substrate types,
and thus will aid efforts to reliably create complex SLB
platforms on a range of substrates.},
Doi = {10.1016/j.cocis.2013.06.004},
Key = {fds263340}
}
@article{fds263341,
Author = {Ferris, RJ and Lin, S and Therezien, M and Yellen, BB and Zauscher,
S},
Title = {Electric double layer formed by polarized ferroelectric thin
films.},
Journal = {Acs Applied Materials & Interfaces},
Volume = {5},
Number = {7},
Pages = {2610-2617},
Year = {2013},
Month = {April},
url = {http://www.ncbi.nlm.nih.gov/pubmed/23484485},
Abstract = {Ferroelectric surfaces can have very high surface charge
densities that can be harnessed for manipulation of charged
colloidal particles and soft matter in aqueous environments.
Here, we report on the electrical double layer (EDL) formed
by polarized ultrasmooth lead zirconium titanate (US-PZT)
thin films in dilute electrolyte solutions. Using colloidal
probe force microscopy (CPFM) measurements, we show that the
ion distribution within the double layer can be changed by
reversing the ferroelectric polarization state of US-PZT.
The interaction force in dilute 1:1 electrolyte solution
between the negatively charged probe and a positive surface
charge (upward polarized) US-PZT thin film is attractive,
while the interaction force is repulsive for a negative
surface charge (downward polarized) film. We modeled these
interactions with a constant-potential EDL model between
dissimilar surfaces with the inclusion of a Stern layer. We
report the surface potentials at the inner and
outer-Helmholtz planes both for polarization states and for
a range of ionic strength solutions. Effects of free-charge
carriers, limitations of the analytical model, and effects
of surface roughness are discussed.},
Doi = {10.1021/am3031954},
Key = {fds263341}
}
@article{fds319132,
Author = {Schulz, BS and Zauscher, S and Ammer, H and Sauter-Louis, C and Hartmann, K},
Title = {Side effects suspected to be related to doxycycline use in
cats.},
Journal = {The Veterinary Record},
Volume = {172},
Number = {7},
Pages = {184},
Year = {2013},
Month = {February},
url = {http://dx.doi.org/10.1136/vr.101031},
Doi = {10.1136/vr.101031},
Key = {fds319132}
}
@article{fds263339,
Author = {Parlak, Z and Biet, C and Zauscher, S},
Title = {Decoupling mass adsorption from fluid viscosity and density
in quartz crystal microbalance measurements using normalized
conductance modeling},
Journal = {Measurement Science and Technology},
Volume = {24},
Number = {8},
Pages = {085301-085301},
Publisher = {IOP Publishing},
Year = {2013},
Month = {January},
ISSN = {0957-0233},
url = {http://dx.doi.org/10.1088/0957-0233/24/8/085301},
Abstract = {We describe the physical understanding of a method which
differentiates between the frequency shift caused by fluid
viscosity and density from that caused by mass adsorption in
the resonance of a quartz crystal resonator. This method
uses the normalized conductance of the crystal to determine
a critical frequency at which the fluid mass and fluid loss
compensate each other. Tracking the shift in this critical
frequency allows us to determine purely mass adsorption on
the crystal. We extended this method to Maxwellian fluids
for understanding the mass adsorption in non-Newtonian
fluids. We validate our approach by real-time mass
adsorption measurements using glycerol and albumin
solutions. © 2013 IOP Publishing Ltd.},
Doi = {10.1088/0957-0233/24/8/085301},
Key = {fds263339}
}
@article{fds263355,
Author = {Hardy, GJ and Nayak, R and Alam, SM and Shapter, JG and Heinrich, F and Zauscher, S},
Title = {Biomimetic supported lipid bilayers with high cholesterol
content formed by α-helical peptide-induced vesicle
fusion.},
Journal = {Journal of Materials Chemistry},
Volume = {22},
Number = {37},
Pages = {19506-19513},
Year = {2012},
Month = {August},
ISSN = {0959-9428},
url = {http://dx.doi.org/10.1039/c2jm32016a},
Abstract = {In this study, we present a technique to create a complex,
high cholesterol-containing supported lipid bilayers (SLBs)
using α-helical (AH) peptide-induced vesicle fusion.
Vesicles consisting of POPC : POPE : POPS : SM : Chol (9.35
: 19.25 : 8.25 : 18.15 : 45.00) were used to form a SLB that
models the native composition of the human immunodeficiency
virus-1 (HIV-1) lipid envelope. In the absence of AH
peptides, these biomimetic vesicles fail to form a complete
SLB. We verified and characterized AH peptide-induced
vesicle fusion by quartz crystal microbalance with
dissipation monitoring, neutron reflectivity, and atomic
force microscopy. Successful SLB formation entailed a
characteristic frequency shift of -35.4 ± 2.0 Hz and a
change in dissipation energy of 1.91 ± 0.52 ×
10<sup>-6</sup>. Neutron reflectivity measurements
determined the SLB thickness to be 49.9 <sup>+1.9</sup><sub>-1.5</sub>
Å, and showed the SLB to be 100 <sup>+0.0</sup><sub>-0.1</sub>%
complete and void of residual AH peptide after washing.
Atomic force microscopy imaging confirmed complete SLB
formation and revealed three distinct domains with no
visible defects. This vesicle fusion technique gives
researchers access to a complex SLB composition with high
cholesterol content and thus the ability to better
recapitulate the native HIV-1 lipid membrane.},
Doi = {10.1039/c2jm32016a},
Key = {fds263355}
}
@article{fds263368,
Author = {Hardy, GJ and Lam, Y and Stewart, SM and Anasti, K and Alam, SM and Zauscher, S},
Title = {Screening the interactions between HIV-1 neutralizing
antibodies and model lipid surfaces.},
Journal = {J Immunol Methods},
Volume = {376},
Number = {1-2},
Pages = {13-19},
Year = {2012},
Month = {February},
url = {http://www.ncbi.nlm.nih.gov/pubmed/22033342},
Abstract = {Our work is motivated by the observation that rare, broadly
neutralizing antibodies (NAbs), 4E10 and 2F5, associate with
HIV-1 lipids as part of a required first step in
neutralization before binding to membrane-proximal antigens.
Subsequently, induction of these types of NAbs may be
limited by immunologic tolerance due to autoreactivity with
host cell membranes. Despite the significance of this lipid
reactivity there is little experimental evidence detailing
NAb-membrane interactions. Simple and efficient screening
assays are needed to select antibodies that have similar
lipid reactivity as known NAbs. To this end we have
developed a surface plasmon resonance (SPR) spectroscopy
based assay that monitors antibody binding to thiol
self-assembled monolayers (SAMs) that replicate salient
lipid surface chemistries and NAb binding to lipid surfaces.
Specifically, we probed the relative importance of charge
and hydrophobicity on antibody-surface interactions. We
found that NAb binding to hydrophobic thiol surfaces was
significantly greater than that of control monoclonal
antibodies (mAbs). Furthermore, we confirmed the importance
of charge-mediated antibody surface interactions, originally
suggested by results from mAb interactions with conventional
lipid vesicle/bilayer surfaces. Our approach, using
self-assembled thiol monolayers that replicate the binding
behavior of NAbs on lipid surfaces, thus provides an
efficient and useful tool to screen interactions of mAbs and
lipid-reactive NAbs.},
Doi = {10.1016/j.jim.2011.10.005},
Key = {fds263368}
}
@article{fds263333,
Author = {Tjong, V and Zhang, J and Chilkoti, A and Zauscher,
S},
Title = {Stimulus-Responsive Polymers as Intelligent Coatings for
Biosensors: Architectures, Response Mechanisms, and
Applications},
Pages = {1-30},
Booktitle = {Intelligent Surfaces in Biotechnology},
Publisher = {JOHN WILEY & SONS INC},
Address = {New York},
Editor = {Textor M. and Grandin M},
Year = {2012},
Month = {February},
url = {http://dx.doi.org/10.1002/9781118181249.ch1},
Doi = {10.1002/9781118181249.ch1},
Key = {fds263333}
}
@article{fds263354,
Author = {Chen, T and Chang, DP and Zhang, J and Jordan, R and Zauscher,
S},
Title = {Manipulating the motion of gold aggregates using
stimulus-responsive patterned polymer brushes as a
motor},
Journal = {Advanced Functional Materials},
Volume = {22},
Number = {2},
Pages = {429-434},
Publisher = {WILEY},
Year = {2012},
Month = {January},
ISSN = {1616-301X},
url = {http://dx.doi.org/10.1002/adfm.201101795},
Abstract = {An important goal and major challenge of material science
and nanotechnology is building nanomotors for manipulating
the motion of nanoparticles (NPs). Here, it is demonstrated
that patterned, stimulus-responsive polymer brush
microstructures can be used as motor arrays to manipulate
the movement of gold NP aggregates in response to external
stimuli that induce a conformational change in the brushes
as the driving force. The motion of NP aggregates in the
out-of-plane direction is achieved with displacements
ranging from nanometers to sub-micrometers. These patterned
polymer-brush microstructures can find applications as
efficient motor arrays and nanosensors, and benefit the
design of more complex nanodevices. Patterned,
stimulus-responsive, "egg-cup"-shaped polymer brush
microstructures can be used as motor arrays to manipulate
the movement of gold nanoparticle (NP) aggregates in
response to external stimuli that induce a conformational
change in the brushes as the driving force. The motion of NP
aggregates in the out-of-plane direction was achieved with
displacements ranging from nanometers to sub-micrometers.
Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA,
Weinheim.},
Doi = {10.1002/adfm.201101795},
Key = {fds263354}
}
@article{fds263353,
Author = {Chen, T and Chang, DP and Jordan, R and Zauscher,
S},
Title = {Colloidal lithography for fabricating patterned
polymer-brush microstructures.},
Journal = {Beilstein Journal of Nanotechnology},
Volume = {3},
Pages = {397-403},
Year = {2012},
Month = {January},
url = {http://www.ncbi.nlm.nih.gov/pubmed/23016144},
Abstract = {We exploit a series of robust, but simple and convenient
colloidal lithography (CL) approaches, using a microsphere
array as a mask or as a guiding template, and combine this
with surface-initiated atom-transfer radical polymerization
(SI-ATRP) to fabricate patterned polymer-brush
microstructures. The advantages of the CL technique over
other lithographic approaches for the fabrication of
patterned polymer brushes are (i) that it can be carried out
with commercially available colloidal particles at a
relatively low cost, (ii) that no complex equipment is
required to create the patterned templates with micro- and
nanoscale features, and (iii) that polymer brush features
are controlled simply by changing the size or chemical
functionality of the microspheres or the
substrate.},
Doi = {10.3762/bjnano.3.46},
Key = {fds263353}
}
@article{fds263356,
Author = {Ferris, R and Yellen, B and Zauscher, S},
Title = {Ferroelectric thin films in fluidic environments: a new
interface for sensing and manipulation of
matter.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {8},
Number = {1},
Pages = {28-35},
Year = {2012},
Month = {January},
url = {http://www.ncbi.nlm.nih.gov/pubmed/22102532},
Abstract = {For decades ferroelectric thin films (FETFs) have been the
focus of research and development for next-generation memory
and semiconductor devices. FETFs are attractive because
their polarization states are highly localized, stable, and
switchable. These unique properties are also attractive for
(bio)molecular sensing and separation applications.
Polarization of both polymer and ceramic FETF results in the
expression of a sustained high, non-Faradaic, surface charge
density. If these surface charges are maintained in aqueous
environments, then the resulting electrostatic forces should
induce the formation of electrolyte gradients and aid in the
localization of charged species to the surface. Recently,
there has been a growing interest in the interfacial
properties of FETFs, specifically how they interact with
liquid or gaseous phases. Recent work has shown that the
FETF polarization state affects adsorption from the gaseous
phase, surface catalysis, and cell growth. Encouraged by
these findings, the use of FETFs in aqueous environments is
explored. After an introduction to FETFs, the growing body
of literature on the FETF interface is reviewed, along with
the limited number of studies demonstrating FETF function in
gas and liquid environments. Finally, the exciting
possibilities that FETFs could bring to interfacial
engineering and lab-on-chip (LOC) device design is
reviewed.},
Doi = {10.1002/smll.201101173},
Key = {fds263356}
}
@article{fds263361,
Author = {Christensen, SE and Coles, JM and Zelenski, NA and Furman, BD and Leddy,
HA and Zauscher, S and Bonaldo, P and Guilak, F},
Title = {Altered trabecular bone structure and delayed cartilage
degeneration in the knees of collagen VI null
mice.},
Journal = {Plos One},
Volume = {7},
Number = {3},
Pages = {e33397},
Year = {2012},
Month = {January},
url = {http://www.ncbi.nlm.nih.gov/pubmed/22448243},
Abstract = {Mutation or loss of collagen VI has been linked to a variety
of musculoskeletal abnormalities, particularly muscular
dystrophies, tissue ossification and/or fibrosis, and hip
osteoarthritis. However, the role of collagen VI in bone and
cartilage structure and function in the knee is unknown. In
this study, we examined the role of collagen VI in the
morphology and physical properties of bone and cartilage in
the knee joint of Col6a1(-/-) mice by micro-computed
tomography (microCT), histology, atomic force microscopy
(AFM), and scanning microphotolysis (SCAMP). Col6a1(-/-)
mice showed significant differences in trabecular bone
structure, with lower bone volume, connectivity density,
trabecular number, and trabecular thickness but higher
structure model index and trabecular separation compared to
Col6a1(+/+) mice. Subchondral bone thickness and mineral
content increased significantly with age in Col6a1(+/+)
mice, but not in Col6a1(-/-) mice. Col6a1(-/-) mice had
lower cartilage degradation scores, but developed early,
severe osteophytes compared to Col6a1(+/+) mice. In both
groups, cartilage roughness increased with age, but neither
the frictional coefficient nor compressive modulus of the
cartilage changed with age or genotype, as measured by AFM.
Cartilage diffusivity, measured via SCAMP, varied minimally
with age or genotype. The absence of type VI collagen has
profound effects on knee joint structure and morphometry,
yet minimal influences on the physical properties of the
cartilage. Together with previous studies showing
accelerated hip osteoarthritis in Col6a1(-/-) mice, these
findings suggest different roles for collagen VI at
different sites in the body, consistent with clinical
data.},
Doi = {10.1371/journal.pone.0033397},
Key = {fds263361}
}
@article{fds319136,
Author = {Hardy, GJ and Alam, M and Shapter, J and Zauscher,
S},
Title = {Visualizing Lipid Reactivity of HIV-1 Antigen and
Neutralizing Antibodies using Atomic Force
Microscopy},
Journal = {Biophysical Journal},
Volume = {102},
Number = {3},
Pages = {303a-303a},
Publisher = {Elsevier BV},
Year = {2012},
Month = {January},
url = {http://dx.doi.org/10.1016/j.bpj.2011.11.1673},
Doi = {10.1016/j.bpj.2011.11.1673},
Key = {fds319136}
}
@article{fds263357,
Author = {Zhang, J and Parlak, Z and Bowers, CM and Oas, T and Zauscher,
S},
Title = {Mapping mechanical properties of organic thin films by
force-modulation microscopy in aqueous media.},
Journal = {Beilstein Journal of Nanotechnology},
Volume = {3},
Pages = {464-474},
Year = {2012},
url = {http://www.ncbi.nlm.nih.gov/pubmed/23019540},
Abstract = {The mechanical properties of organic and biomolecular thin
films on surfaces play an important role in a broad range of
applications. Although force-modulation microscopy (FMM) is
used to map the apparent elastic properties of such films
with high lateral resolution in air, it has rarely been
applied in aqueous media. In this letter we describe the use
of FMM to map the apparent elastic properties of
self-assembled monolayers and end-tethered protein thin
films in aqueous media. Furthermore, we describe a simple
analysis of the contact mechanics that enables the selection
of FMM imaging parameters and thus yields a reliable
interpretation of the FMM image contrast.},
Doi = {10.3762/bjnano.3.53},
Key = {fds263357}
}
@article{fds263371,
Author = {Ferris, R and Hucknall, A and Kwon, BS and Chen, T and Chilkoti, A and Zauscher, S},
Title = {Field-induced nanolithography for patterning of non-fouling
polymer brush surfaces.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {7},
Number = {21},
Pages = {3032-3037},
Year = {2011},
Month = {November},
url = {http://www.ncbi.nlm.nih.gov/pubmed/21901825},
Doi = {10.1002/smll.201100923},
Key = {fds263371}
}
@article{fds263370,
Author = {Chen, T and Jordan, R and Zauscher, S},
Title = {Dynamic microcontact printing for patterning polymer-brush
microstructures.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {7},
Number = {15},
Pages = {2148-2152},
Year = {2011},
Month = {August},
url = {http://www.ncbi.nlm.nih.gov/pubmed/21598381},
Doi = {10.1002/smll.201100354},
Key = {fds263370}
}
@article{ISI:000291354200009,
Author = {Chen, T and Jordan, R and Zauscher, S},
Title = {Polymer brush patterning using self-assembled microsphere
monolayers as microcontact printing stamps},
Journal = {Soft Matter},
Volume = {7},
Number = {12},
Pages = {5532-5535},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2011},
Month = {June},
ISSN = {1744-683X},
url = {http://dx.doi.org/10.1039/c1sm05474k},
Abstract = {Self-assembled microsphere monolayers (SMMs) hold
significant promise for micro- and nanopatterning. Here we
exploit, for the first time, SMMs as stamps for microcontact
printing (μCP) and demonstrate this to fabricate patterned
initiator templates that can subsequently be amplified into
polymer brushes by surface initiated atom transfer radical
polymerization (SI-ATRP). SMM stamps avoid the need for
expensive and sophisticated instrumentation in pattern
generation, and provide a broad range of accessible surface
chemistries and pitch size control. © 2011 The Royal
Society of Chemistry.},
Doi = {10.1039/c1sm05474k},
Key = {ISI:000291354200009}
}
@article{fds263334,
Author = {Chen, T and Zhang, J and Garcia, A and Ducker, R and Zauscher,
S},
Title = {Nanopatterning of Polymer Brush Thin Films by Electron-Beam
Lithography and Scanning Probe Lithography},
Volume = {1},
Pages = {501-518},
Booktitle = {Functional Polymer Films},
Publisher = {Wiley-VCH Verlag GmbH & Co. KGaA},
Address = {New York},
Editor = {Advincula, R. and Knoll, W.},
Year = {2011},
Month = {June},
url = {http://dx.doi.org/10.1002/9783527638482.ch14},
Doi = {10.1002/9783527638482.ch14},
Key = {fds263334}
}
@article{ISI:000291133400001,
Author = {Chen, T and Jordan, R and Zauscher, S},
Title = {Extending micro-contact printing for patterning complex
polymer brush microstructures},
Journal = {Polymer},
Volume = {52},
Number = {12},
Pages = {2461-2467},
Publisher = {Elsevier BV},
Year = {2011},
Month = {May},
ISSN = {0032-3861},
url = {http://dx.doi.org/10.1016/j.polymer.2011.04.008},
Abstract = {As a fast developing soft lithographic technique, the
development of micro-contact printing (μCP) has exceeded
the original aim of replicating poly(dimethylsiloxane)
(PDMS) stamp patterns. Here we exploited several extended
μCP strategies with various printing conditions (over-force
or swelling induced physical deformation, and UV-Ozone
treated chemical surface modification to a PDMS stamp),
combining with surface initiated atom transfer radical
polymerization (SI-ATRP), to pattern complex
poly(N-isopropylacrylamide) (PNIPAAM) brush microstructures.
These series of μCP strategies avoid the need for expensive
and sophisticated instrumentation in patterning complex
polymer brush microstructures that do not exist on the
original PDMS stamp. © 2011 Elsevier Ltd. All rights
reserved.},
Doi = {10.1016/j.polymer.2011.04.008},
Key = {ISI:000291133400001}
}
@article{ISI:000289341500050,
Author = {Yang, Y and Erb, RM and Wiley, BJ and Zauscher, S and Yellen,
BB},
Title = {Imaginary magnetic tweezers for massively parallel surface
adhesion spectroscopy.},
Journal = {Nano Letters},
Volume = {11},
Number = {4},
Pages = {1681-1684},
Year = {2011},
Month = {April},
ISSN = {1530-6984},
url = {http://www.ncbi.nlm.nih.gov/pubmed/21417363},
Abstract = {A massively parallel magnetic tweezer system has been
constructed that utilizes the self-repulsion of colloidal
beads from a planar interface via a magnetic dipole image
force. Self-repulsion enables the application of a uniform
magnetic force to thousands of beads simultaneously, which
permits the measurement of unbinding histograms at the
lowest loading rates ever tested. The adhesion of 9.8 μm
polystyrene beads to a fluorocarbon, PEG, and UV-irradiated
PEG surfaces were measured between 10(-3)-10(0) pN/s force
loading rates, revealing the presence of both kinetic and
quasi-equilibrium unbinding regimes.},
Doi = {10.1021/nl200189w},
Key = {ISI:000289341500050}
}
@article{fds194119,
Author = {Parlak, Z. and Zhang, J. and Franch, B. and Morris, C. and Oas, T. and Zauscher, S.},
Title = {Imaging Dynamic Mechanical Properties of Biomolecules by
Force Modulation Microscopy},
Journal = {Proceedings of the 1st International Conference on Smart
Polymer Systems},
Year = {2011},
Key = {fds194119}
}
@article{fds263369,
Author = {Malmsten, M and Zauscher, S},
Title = {Colloids and surfaces in biology},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {15},
Number = {6},
Pages = {393-394},
Publisher = {Elsevier BV},
Year = {2010},
Month = {December},
ISSN = {1359-0294},
url = {http://dx.doi.org/10.1016/j.cocis.2010.08.001},
Doi = {10.1016/j.cocis.2010.08.001},
Key = {fds263369}
}
@article{ISI:000284520000003,
Author = {Coles, JM and Chang, DP and Zauscher, S},
Title = {Molecular mechanisms of aqueous boundary lubrication by
mucinous glycoproteins},
Journal = {Current Opinion in Colloid & Interface Science},
Volume = {15},
Number = {6},
Pages = {406-416},
Publisher = {Elsevier BV},
Year = {2010},
Month = {December},
ISSN = {1359-0294},
url = {http://dx.doi.org/10.1016/j.cocis.2010.07.002},
Abstract = {Mucins have long been recognized as instrumental to
biolubrication but the molecular details of their
lubrication mechanisms have only been explored relatively
recently. The glycoprotein PRG4, also known as lubricin,
shares many features with mucins and appears to lubricate
through similar mechanisms. A number of studies have
contributed to a more in-depth understanding of mucin
adsorption and layer formation on surfaces and the
mechanisms by which these layers lubricate. Although
mucinous glycoproteins differ in their aggregation
properties, their adsorption behaviors on surfaces, and in
their ability to reduce friction, they share important
similarities favorable for lubrication. They are highly
hydrated, they adsorb strongly to a broad range of surfaces,
and the layers they form are both sterically and
electrostatically repulsive, all attributes thought to
contribute to boundary lubrication. They also hydrophilize
hydrophobic surfaces, promoting the formation of aqueous
fluid films that can lower friction at already relatively
low sliding speeds. In this paper we briefly review current
knowledge of mucin adsorption and lubrication, with a focus
on recent advances. © 2010 Elsevier Ltd.},
Doi = {10.1016/j.cocis.2010.07.002},
Key = {ISI:000284520000003}
}
@article{ISI:000284343700036,
Author = {Coles, JM and Blum, JJ and Jay, GD and Darling, EM and Guilak, F and Zauscher, S},
Title = {Corrigendum to In situ friction measurement on murine
cartilage by atomic force microscopy [J. Biomech. 41, 3,
(2008) 541-548]},
Journal = {Journal of Biomechanics},
Volume = {43},
Number = {14},
Pages = {2866},
Publisher = {Elsevier BV},
Year = {2010},
Month = {October},
ISSN = {0021-9290},
url = {http://dx.doi.org/10.1016/j.jbiomech.2010.09.020},
Doi = {10.1016/j.jbiomech.2010.09.020},
Key = {ISI:000284343700036}
}
@inproceedings{ISI:000290920600056,
Author = {Zhao, Y and Chen, T and Zhang, X and Zauscher, S and Chen,
CH},
Title = {Development of an adaptive vapor chamber with
thermoresponsive polymer coating},
Journal = {Proceedings of the Asme Micro/Nanoscale Heat and Mass
Transfer International Conference 2009, Mnhmt2009},
Volume = {3},
Pages = {395-398},
Booktitle = {PROCEEDINGS OF THE ASME MICRO/NANOSCALE HEAT AND MASS
TRANSFER INTERNATIONAL CONFERENCE, VOL 3},
Publisher = {ASME},
Organization = {ASME Nanotechnol Inst},
Institution = {ASME Nanotechnol Inst},
Year = {2010},
Month = {July},
ISBN = {978-0-7918-4391-8},
url = {http://dx.doi.org/10.1115/MNHMT2009-18276},
Abstract = {We propose a novel concept for an adaptive vapor chamber
using a thermoresponsive polymer coating to enhance heat
transfer and reduce local thermal gradients. By coating the
wick structures with stimulus-responsive polymer brushes
with an upper critical solution temperature (UCST), i the
hotter surface becomes more wettable than the colder
surface. The smaller contact angle at higher temperature
generates larger capillary forces and promotes stronger
return flow toward the hotspots. In this paper, we present
our ; progress toward developing the adaptive vapor chamber.
We have grafted poly(2-(meth-acryloyloxy)ethyl(dimethyl(3-sulfopropyl)
ammonium hydroxide) (PMEDSAH) brushes on silica wafers, and
the PMEDSAH polymer coating exhibits UCST properties with
stable and tunable wettability. We have captured infrared
images of the evaporator with steady and transient heating,
and developed a thermographic technique that can be used to
test the adaptive wick functionality in a vapor chamber.
Copyright © 2009 by ASME.},
Doi = {10.1115/MNHMT2009-18276},
Key = {ISI:000290920600056}
}
@article{fds319137,
Author = {Chen, T and Chang, DP and Zauscher, S},
Title = {Polymer brushes: Fabrication of Patterned Polymer Brushes on
Chemically Active Surfaces by in situ Hydrogen-Bond-Mediated
Attachment of an Initiator (Small 14/2010).},
Journal = {Small},
Volume = {6},
Number = {14},
Year = {2010},
Month = {July},
url = {http://dx.doi.org/10.1002/smll.201090044},
Doi = {10.1002/smll.201090044},
Key = {fds319137}
}
@article{ISI:000280633900008,
Author = {Chen, T and Chang, DP and Zauscher, S},
Title = {Fabrication of patterned polymer brushes on chemically
active surfaces by in situ hydrogen-bond-mediated attachment
of an initiator.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {6},
Number = {14},
Pages = {1504-1508},
Year = {2010},
Month = {July},
ISSN = {1613-6810},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20572261},
Doi = {10.1002/smll.200902119},
Key = {ISI:000280633900008}
}
@article{ISI:000278913500013,
Author = {Darling, EM and Wilusz, RE and Bolognesi, MP and Zauscher, S and Guilak,
F},
Title = {Spatial mapping of the biomechanical properties of the
pericellular matrix of articular cartilage measured in situ
via atomic force microscopy.},
Journal = {Biophysical Journal},
Volume = {98},
Number = {12},
Pages = {2848-2856},
Year = {2010},
Month = {June},
ISSN = {0006-3495},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20550897},
Abstract = {In articular cartilage, chondrocytes are surrounded by a
narrow region called the pericellular matrix (PCM), which is
biochemically, structurally, and mechanically distinct from
the bulk extracellular matrix (ECM). Although multiple
techniques have been used to measure the mechanical
properties of the PCM using isolated chondrons (the PCM with
enclosed cells), few studies have measured the biomechanical
properties of the PCM in situ. The objective of this study
was to quantify the in situ mechanical properties of the PCM
and ECM of human, porcine, and murine articular cartilage
using atomic force microscopy (AFM). Microscale elastic
moduli were quantitatively measured for a region of interest
using stiffness mapping, or force-volume mapping, via AFM.
This technique was first validated by means of elastomeric
models (polyacrylamide or polydimethylsiloxane) of a soft
inclusion surrounded by a stiff medium. The elastic
properties of the PCM were evaluated for regions surrounding
cell voids in the middle/deep zone of sectioned articular
cartilage samples. ECM elastic properties were evaluated in
regions visually devoid of PCM. Stiffness mapping
successfully depicted the spatial arrangement of moduli in
both model and cartilage surfaces. The modulus of the PCM
was significantly lower than that of the ECM in human,
porcine, and murine articular cartilage, with a ratio of PCM
to ECM properties of approximately 0.35 for all species.
These findings are consistent with previous studies of
mechanically isolated chondrons, and suggest that stiffness
mapping via AFM can provide a means of determining
microscale inhomogeneities in the mechanical properties of
articular cartilage in situ.},
Doi = {10.1016/j.bpj.2010.03.037},
Key = {ISI:000278913500013}
}
@article{ISI:000276553300007,
Author = {Chen, T and Chang, DP and Liu, T and Desikan, R and Datar, R and Thundat,
T and Berger, R and Zauscher, S},
Title = {Glucose-responsive polymer brushes for microcantilever
sensing},
Journal = {Journal of Materials Chemistry},
Volume = {20},
Number = {17},
Pages = {3391-3395},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2010},
Month = {June},
ISSN = {0959-9428},
url = {http://hdl.handle.net/10161/4121 Duke open
access},
Abstract = {Glucose responsive polymer brushes were synthesized on gold
substrates and microcantilever arrays. The response
properties of these brushes were evaluated by exposing them
to different glucose concentrations for a range of pH
values. This work demonstrates the potential for polymer
brush-functionalized micromechanical cantilevers as glucose
detectors. Furthermore, the work demonstrates that
stimulus-responsive polymer brushes on micromechanical
cantilevers have a significantly larger bending response due
to glucose binding compared with self-assembled monolayers.
© The Royal Society of Chemistry 2010.},
Doi = {10.1039/b925583d},
Key = {ISI:000276553300007}
}
@article{ISI:000279432500015,
Author = {Coles, JM and Zhang, L and Blum, JJ and Warman, ML and Jay, GD and Guilak,
F and Zauscher, S},
Title = {Loss of cartilage structure, stiffness, and frictional
properties in mice lacking PRG4.},
Journal = {Arthritis and Rheumatism},
Volume = {62},
Number = {6},
Pages = {1666-1674},
Year = {2010},
Month = {June},
ISSN = {0004-3591},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20191580},
Abstract = {<h4>Objective</h4>To assess the role of the glycoprotein
PRG4 in joint lubrication and chondroprotection by measuring
friction, stiffness, surface topography, and subsurface
histology of the hip joints of Prg4(-/-) and wild-type (WT)
mice.<h4>Methods</h4>Friction and elastic modulus were
measured in cartilage from the femoral heads of Prg4(-/-)
and WT mice ages 2, 4, 10, and 16 weeks using atomic force
microscopy, and the surface microstructure was imaged.
Histologic sections of each femoral head were stained and
graded.<h4>Results</h4>Histologic analysis of the joints of
Prg4(-/-) mice showed an enlarged, fragmented surface layer
of variable thickness with Safranin O-positive formations
sometimes present, a roughened underlying articular
cartilage surface, and a progressive loss of pericellular
proteoglycans. Friction was significantly higher on
cartilage of Prg4(-/-) mice at age 16 weeks, but
statistically significant differences in friction were not
detected at younger ages. The elastic modulus of the
cartilage was similar between cartilage surfaces of
Prg4(-/-) and WT mice at young ages, but cartilage of WT
mice showed increasing stiffness with age, with
significantly higher moduli than cartilage of Prg4(-/-) mice
at older ages.<h4>Conclusion</h4>Deletion of the gene Prg4
results in significant structural and biomechanical changes
in the articular cartilage with age, some of which are
consistent with osteoarthritic degeneration. These findings
suggest that PRG4 plays a significant role in preserving
normal joint structure and function.},
Doi = {10.1002/art.27436},
Key = {ISI:000279432500015}
}
@article{ISI:000277710700004,
Author = {Huang, X and Zauscher, S and Klitzman, B and Truskey, GA and Reichert,
WM and Kenan, DJ and Grinstaff, MW},
Title = {Peptide interfacial biomaterials improve endothelial cell
adhesion and spreading on synthetic polyglycolic acid
materials.},
Journal = {Ann Biomed Eng},
Volume = {38},
Number = {6},
Pages = {1965-1976},
Year = {2010},
Month = {June},
ISSN = {0090-6964},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20300848},
Abstract = {Resorbable scaffolds such as polyglycolic acid (PGA) are
employed in a number of clinical and tissue engineering
applications owing to their desirable property of allowing
remodeling to form native tissue over time. However, native
PGA does not promote endothelial cell adhesion. Here we
describe a novel treatment with hetero-bifunctional peptide
linkers, termed "interfacial biomaterials" (IFBMs), which
are used to alter the surface of PGA to provide appropriate
biological cues. IFBMs couple an affinity peptide for the
material with a biologically active peptide that promotes
desired cellular responses. One such PGA affinity peptide
was coupled to the integrin binding domain, Arg-Gly-Asp
(RGD), to build a chemically synthesized bimodular 27 amino
acid peptide that mediated interactions between PGA and
integrin receptors on endothelial cells. Quartz crystal
microbalance with dissipation monitoring (QCMD) was used to
determine the association constant (K (A) 1 x 10(7) M(-1))
and surface thickness (~3.5 nm). Cell binding studies
indicated that IFBM efficiently mediated adhesion,
spreading, and cytoskeletal organization of endothelial
cells on PGA in an integrin-dependent manner. We show that
the IFBM peptide promotes a 200% increase in endothelial
cell binding to PGA as well as 70-120% increase in cell
spreading from 30 to 60 minutes after plating.},
Doi = {10.1007/s10439-010-9986-5},
Key = {ISI:000277710700004}
}
@article{ISI:000273810600012,
Author = {Stuart, MAC and Huck, WTS and Genzer, J and Müller, M and Ober, C and Stamm, M and Sukhorukov, GB and Szleifer, I and Tsukruk, VV and Urban,
M and Winnik, F and Zauscher, S and Luzinov, I and Minko,
S},
Title = {Emerging applications of stimuli-responsive polymer
materials.},
Journal = {Nature Materials},
Volume = {9},
Number = {2},
Pages = {101-113},
Year = {2010},
Month = {February},
ISSN = {1476-1122},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20094081},
Abstract = {Responsive polymer materials can adapt to surrounding
environments, regulate transport of ions and molecules,
change wettability and adhesion of different species on
external stimuli, or convert chemical and biochemical
signals into optical, electrical, thermal and mechanical
signals, and vice versa. These materials are playing an
increasingly important part in a diverse range of
applications, such as drug delivery, diagnostics, tissue
engineering and 'smart' optical systems, as well as
biosensors, microelectromechanical systems, coatings and
textiles. We review recent advances and challenges in the
developments towards applications of stimuli-responsive
polymeric materials that are self-assembled from
nanostructured building blocks. We also provide a critical
outline of emerging developments.},
Doi = {10.1038/nmat2614},
Key = {ISI:000273810600012}
}
@article{ISI:000274776300005,
Author = {Chen, T and Ferris, R and Zhang, J and Ducker, R and Zauscher,
S},
Title = {Stimulus-responsive polymer brushes on surfaces:
Transduction mechanisms and applications},
Journal = {Progress in Polymer Science},
Volume = {35},
Number = {1-2, SI},
Pages = {94-112},
Publisher = {Elsevier BV},
Year = {2010},
Month = {January},
ISSN = {0079-6700},
url = {http://dx.doi.org/10.1016/j.progpolymsci.2009.11.004},
Abstract = {Stimulus-responsive polymer brushes (SRPBs) exhibit a change
in conformation and structure, often accompanied by a
noticeable change in surface energy, due to an external
stimulus such as a change in solvent composition,
temperature, pH, ionic strength, light, or mechanical
stress. SRPBs offer exciting and new possibilities to
fabricate adaptive or responsive smart materials. This
review summarizes selected, recent progress in SRPB
applications in the field of surface wettability switching,
mechanical actuation, and environmental sensing.
Furthermore, we review selected papers from an emerging area
in which SRPBs are used for nano- and microfabrication. (C)
2009 Elsevier Ltd. All rights reserved.},
Doi = {10.1016/j.progpolymsci.2009.11.004},
Key = {ISI:000274776300005}
}
@article{fds194118,
Author = {Chen, T. and Zauscher, S.},
Title = {Nanopatterning of Functional Polymer Brush Thin
Films},
Journal = {Proceedings of the 1st International Conference on Smart
Polymer Systems},
Year = {2010},
Key = {fds194118}
}
@inproceedings{ISI:000280089000533,
Author = {Wilusz, RE and Darling, EM and Bolognesi, MP and Zauscher, S and Guilak,
F},
Title = {The inhomogeneous mechanical properties of the pericellular
matrix of articular cartilage measured in situ by atomic
force microscopy},
Journal = {Proceedings of the Asme Summer Bioengineering Conference
2009, Sbc2009},
Number = {PART B},
Pages = {1065-1066},
Booktitle = {PROCEEDINGS OF THE ASME SUMMER BIOENGINEERING CONFERENCE -
2009, PT A AND B},
Publisher = {ASME},
Organization = {ASME Bioengn Div},
Institution = {ASME Bioengn Div},
Year = {2009},
Month = {December},
ISBN = {978-0-7918-4891-3},
url = {http://dx.doi.org/10.1115/SBC2009-206403},
Doi = {10.1115/SBC2009-206403},
Key = {ISI:000280089000533}
}
@article{ISI:000269493300009,
Author = {Chang, DP and Abu-Lail, NI and Coles, JM and Guilak, F and Jay, GD and Zauscher, S},
Title = {Friction Force Microscopy of Lubricin and Hyaluronic Acid
between Hydrophobic and Hydrophilic Surfaces.},
Journal = {Soft Matter},
Volume = {5},
Number = {18},
Pages = {3438-3445},
Year = {2009},
Month = {September},
ISSN = {1744-683X},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20936046},
Abstract = {Lubricin and hyaluronic acid (HA), molecular constituents of
synovial fluid, have long been theorized to play a role in
joint lubrication and wear protection. While lubricin has
been shown to function as a boundary lubricant, conflicting
evidence exists as to the boundary lubricating ability of
hyaluronic acid. Here, we use colloidal force microscopy to
explore the friction behavior of these two molecules on the
microscale between chemically uniform hydrophilic
(hydroxyl-terminated) and hydrophobic (methyl-terminated)
surfaces in physiological buffer solution. Behaviors on both
surfaces are physiologically relevant since the
heterogeneous articular cartilage surface contains both
hydrophilic and hydrophobic elements. Friction between
hydrophobic surfaces was initially high (μ=1.1, at 100nN of
applied normal load) and was significantly reduced by
lubricin addition while friction between hydrophilic
surfaces was initially low (μ=0.1) and was slightly
increased by lubricin addition. At lubricin concentrations
above 200 µg/ml, friction behavior on the two surfaces was
similar (μ=0.2) indicating that nearly all interaction
between the two surfaces was between adsorbed lubricin
molecules rather than between the surfaces themselves. In
contrast, addition of HA did not appreciably alter the
frictional behavior between the model surfaces. No
synergistic effect on friction behavior was seen in a
physiological mixture of lubricin and HA. Lubricin can
equally mediate the frictional response between both
hydrophilic and hydrophobic surfaces, likely fully
preventing direct surface-to-surface contact at sufficient
concentrations, whereas HA provides considerably less
boundary lubrication.},
Doi = {10.1039/b907155e},
Key = {ISI:000269493300009}
}
@article{ISI:000270168900013,
Author = {Darling, EM and Pritchett, PE and Evans, BA and Superfine, R and Zauscher, S and Guilak, F},
Title = {Mechanical properties and gene expression of chondrocytes on
micropatterned substrates following dedifferentiation in
monolayer.},
Journal = {Cellular and Molecular Bioengineering},
Volume = {2},
Number = {3},
Pages = {395-404},
Year = {2009},
Month = {August},
ISSN = {1865-5025},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20625462},
Abstract = {Chondrocytes in articular cartilage normally exhibit high
expression of collagen II and aggrecan but rapidly
dedifferentiate to a fibroblastic phenotype if passaged in
culture. Previous studies have suggested that the loss of
chondrocyte phenotype is associated with changes in the
structure of the F-actin cytoskeleton, which also controls
cell mechanical properties. In this study, we examined how
dedifferentiation in monolayer influences the mechanical
properties of chondrocytes isolated from different zones of
articular cartilage. Atomic force microscopy was used to
measure the mechanical properties of superficial and
middle/deep zone chondrocytes as they underwent serial
passaging and subsequent growth on fibronectin-coated,
micropatterned self-assembled monolayers (MSAMs) that
restored a rounded cell shape in 2D culture. Chondrocytes
exhibited significant increases in elastic and viscoelastic
moduli with dedifferentiation in culture. These changes were
only partially ameliorated by the restoration of a rounded
shape on micropatterned surfaces. Furthermore, intrinsic
zonal differences in cell mechanical properties were rapidly
lost with passage. These findings indicate that cell
mechanical properties may provide additional measures of
phenotypic expression of chondrocytes as they undergo
dedifferentiation and possibly redifferentiation in
culture.},
Doi = {10.1007/s12195-009-0077-3},
Key = {ISI:000270168900013}
}
@article{ISI:000266976300007,
Author = {Hucknall, Angus and Simnick, Andrew J. and Hill, Ryan T. and Chilkoti, Ashutosh and Garcia, Andres and Johannes, Matthew
S. and Clark, Robert L. and Zauscher, Stefan and Ratner,
Buddy D.},
Title = {Versatile synthesis and micropatterning of nonfouling
polymer brushes on the wafer scale},
Journal = {BIOINTERPHASES},
Volume = {4},
Number = {2},
Pages = {FA50-FA57},
Year = {2009},
Month = {June},
ISSN = {1559-4106},
url = {http://dx.doi.org/10.1116/1.3151968},
Abstract = {In this article, the authors describe new approaches to
synthesize and pattern surfaces with poly{[}oligo(ethylene
glycol) methyl methacrylate] (POEGMA) polymer brushes
synthesized by surface-initiated atom transfer radical
polymerization. These patterned coatings confer
``nonfouling{''} properties protein and cell resistance-to
the surface in a biological milieu. The versatile routes for
the synthesis of POEGMA demonstrated here offer clear
advantages over other techniques previously used in terms of
their simplicity, reliability, and ability to pattern
large-area substrates. They also demonstrate that POEGMA
polymer brushes can be patterned directly by
photolithography, plasma ashing, and reactive ion etching to
create patterns at the micro- and nanoscale over large areas
with high throughput and repeatability, while preserving the
protein and cell resistance of the POEGMA
brush.},
Doi = {10.1116/1.3151968},
Key = {ISI:000266976300007}
}
@article{ISI:000266976300001,
Author = {Zauscher, Stefan and Chilkoti, Ashutosh},
Title = {Biological Applications of Polymer Brushes},
Journal = {BIOINTERPHASES},
Volume = {4},
Number = {2},
Pages = {FA1-FA2},
Year = {2009},
Month = {June},
ISSN = {1559-4106},
url = {http://dx.doi.org/10.1116/1.3149787},
Doi = {10.1116/1.3149787},
Key = {ISI:000266976300001}
}
@booklet{Hucknall09,
Author = {Hucknall, A and Simnick, AJ and Hill, RT and Chilkoti, A and Garcia, A and Johannes, MS and Clark, RL and Zauscher, S and Ratner,
BD},
Title = {Versatile synthesis and micropatterning of nonfouling
polymer brushes on the wafer scale.},
Journal = {Biointerphases},
Volume = {4},
Number = {2},
Pages = {FA50-FA57},
Year = {2009},
Month = {June},
ISSN = {1559-4106},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20408717},
Abstract = {In this article, the authors describe new approaches to
synthesize and pattern surfaces with poly[oligo(ethylene
glycol) methyl methacrylate] (POEGMA) polymer brushes
synthesized by surface-initiated atom transfer radical
polymerization. These patterned coatings confer "nonfouling"
properties protein and cell resistance-to the surface in a
biological milieu. The versatile routes for the synthesis of
POEGMA demonstrated here offer clear advantages over other
techniques previously used in terms of their simplicity,
reliability, and ability to pattern large-area substrates.
They also demonstrate that POEGMA polymer brushes can be
patterned directly by photolithography, plasma ashing, and
reactive ion etching to create patterns at the micro- and
nanoscale over large areas with high throughput and
repeatability, while preserving the protein and cell
resistance of the POEGMA brush.},
Doi = {10.1116/1.3151968},
Key = {Hucknall09}
}
@booklet{Zauscher09,
Author = {Zauscher, S and Chilkoti, A},
Title = {Biological applications of polymer brushes.
Preface.},
Journal = {Biointerphases},
Volume = {4},
Number = {2},
Pages = {FA1-FA2},
Year = {2009},
Month = {June},
ISSN = {1559-4106},
url = {http://www.ncbi.nlm.nih.gov/pubmed/20408712},
Doi = {10.1116/1.3149787},
Key = {Zauscher09}
}
@article{ISI:000266287600007,
Author = {Chen, Tao and Zhong, Jianming and Chang, Debby P. and Carcia, Andres and Zauscher, Stefan},
Title = {Fabrication of Micropatterned Stimulus-Responsive
Polymer-Brush `Anemone'},
Journal = {ADVANCED MATERIALS},
Volume = {21},
Number = {18},
Pages = {1825+},
Year = {2009},
Month = {May},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.200802484},
Abstract = {A simple strategy to fabricate stimulus-responsive patterned
PNIPAAM-brush microstructures ('anemones') is presented. The
size of the microstructures can be adjusted by setting the
composition of thiol and the contact pressure. We
demonstrate that the patterned PNIPAAM-brush microstructures
have a triggerable and reversible conformation transition,
and can potentially be used as microcontainers to reversibly
dock and release microparticles.},
Doi = {10.1002/adma.200802484},
Key = {ISI:000266287600007}
}
@booklet{Chen09,
Author = {Chen, T and Zhong, JM and Chang, DP and Carcia, A and Zauscher,
S},
Title = {Fabrication of Micropatterned Stimulus-Responsive
Polymer-Brush 'Anemone'},
Journal = {Advanced Materials (Deerfield Beach, Fla.)},
Volume = {21},
Number = {18},
Pages = {1825-+},
Publisher = {WILEY},
Year = {2009},
Month = {May},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.200802484},
Abstract = {A simple strategy to fabricate stimulus-responsive patterned
PNIPAAM-brush microstructures ('anemones') is presented. The
size of the microstructures can be adjusted by setting the
composition of thiol and the contact pressure. We
demonstrate that the patterned PNIPAAM-brush microstructures
have a triggerable and reversible conformation transition,
and can potentially be used as microcontainers to reversibly
dock and release microparticles.},
Doi = {10.1002/adma.200802484},
Key = {Chen09}
}
@article{ISI:000207857807610,
Author = {Chen, T and Zauscher, S},
Title = {Fabrication of novel polymer brush microstructures using
microcontact printing as a tool},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {237},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2009},
Month = {March},
ISSN = {0065-7727},
url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000207857807610&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92},
Key = {ISI:000207857807610}
}
@article{ISI:000207857803154,
Author = {Dyer, DJ and Wong, VN and Mitrovic, B and Kinsel, GR and Zauscher,
S},
Title = {Responsive polymer brush nanosponges},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {237},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2009},
Month = {March},
ISSN = {0065-7727},
url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000207857803154&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92},
Key = {ISI:000207857803154}
}
@article{ISI:000264047700006,
Author = {Standulescu, Ilinca and Dolbow, John E. and Zauscher,
Stefan},
Title = {Computational modeling of surface phenomena in soft-wet
materials},
Journal = {INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES},
Volume = {46},
Number = {6},
Pages = {1334-1344},
Year = {2009},
Month = {March},
ISSN = {0020-7683},
url = {http://dx.doi.org/10.1016/j.ijsolstr.2008.11.007},
Abstract = {We consider the problem of extracting tribological
information from experimental observations of contact with
soft-wet materials. Particular attention is placed on
simulating the response of two rotating cylinders of soft
specimens placed in frictional contact, with a variable
coefficient of friction dependent on the relative sliding
velocity. The bulk behavior is modeled by means of a finite
deformation viscoelasticity formulation, with constitutive
parameters taken to be representative of hydrogels. We focus
on the modeling of the surface behavior and employ a
mortar-finite element contact formulation. Through a series
of numerical studies, we demonstrate the strong sensitivity
of the results to the choice of interfacial constitutive
parameters. The difficulties of extracting such parameters
using only experimental data and approximate analytical
expressions are also examined. (C) 2008 Elsevier Ltd. All
rights reserved.},
Doi = {10.1016/j.ijsolstr.2008.11.007},
Key = {ISI:000264047700006}
}
@booklet{Standulescu09,
Author = {Stanciulescu, I and Dolbow, JE and Zauscher, S},
Title = {Computational modeling of surface phenomena in soft-wet
materials},
Journal = {International Journal of Solids and Structures},
Volume = {46},
Number = {6},
Pages = {1334-1344},
Publisher = {Elsevier BV},
Year = {2009},
Month = {March},
ISSN = {0020-7683},
url = {http://dx.doi.org/10.1016/j.ijsolstr.2008.11.007},
Abstract = {We consider the problem of extracting tribological
information from experimental observations of contact with
soft-wet materials. Particular attention is placed on
simulating the response of two rotating cylinders of soft
specimens placed in frictional contact, with a variable
coefficient of friction dependent on the relative sliding
velocity. The bulk behavior is modeled by means of a finite
deformation viscoelasticity formulation, with constitutive
parameters taken to be representative of hydrogels. We focus
on the modeling of the surface behavior and employ a
mortar-finite element contact formulation. Through a series
of numerical studies, we demonstrate the strong sensitivity
of the results to the choice of interfacial constitutive
parameters. The difficulties of extracting such parameters
using only experimental data and approximate analytical
expressions are also examined. © 2008 Elsevier Ltd. All
rights reserved.},
Doi = {10.1016/j.ijsolstr.2008.11.007},
Key = {Standulescu09}
}
@article{ISI:000262827400030,
Author = {Wong, Ven Ney and Fernando, Ganga and Wagner, Audrey R. and Zhang, Jianming and Kinsel, Gary R. and Zauscher, Stefan and Dyer, Daniel J.},
Title = {Separation of Peptides with Polyionic Nanosponges for
MALDI-MS Analysis},
Journal = {LANGMUIR},
Volume = {25},
Number = {3},
Pages = {1459-1465},
Year = {2009},
Month = {February},
ISSN = {0743-7463},
url = {http://dx.doi.org/10.1021/la802723r},
Abstract = {A polymer brush consisting of 70\% poly(N-isopropylacrylamide)
(PNIPAAM) and 30\% polymethacrylic acid (PMAA) was
synthesized from gold substrates with a ``grafting from{''}
AIBN-type free-radical initiator. Fractionation of two
peptides, bradykinin and buccalin, was accomplished in less
than 120 s by placing a 30 pM (pH similar to 6.2) droplet
onto the polymer brush substrate. The eluant containing the
anionic buccalin is pipetted away for MALDI analysis while
the cationic bradykinin adsorbed to the swollen anionic
brush and was subsequently released by adding a droplet of
formic acid to the substrate. This caused the brush to
collapse and release the bradykinin, much like squeezing a
sponge; these nanosponge substrates exhibited very high
loading capacity (>2.0 mg/mL compared to
plasma-polymer-modified MALDI substrates. Ellipsometric
measurements showed that complementary peptides adsorb
rapidly while those of the same charge do not, and MALDI-MS
analysis of the two fractions showed separation of both
peptides. The adsorption of bradykinin was monitored over
time, and 85\% of the peptide had been adsorbed to the
nanosponge in 1 min from a 0.5 mg/mL aqueous
solution.},
Doi = {10.1021/la802723r},
Key = {ISI:000262827400030}
}
@booklet{Wong09,
Author = {Wong, VN and Fernando, G and Wagner, AR and Zhang, J and Kinsel, GR and Zauscher, S and Dyer, DJ},
Title = {Separation of Peptides with Polyionic Nanosponges for
MALDI-MS Analysis},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {25},
Number = {3},
Pages = {1459-1465},
Year = {2009},
Month = {February},
ISSN = {0743-7463},
url = {http://www.ncbi.nlm.nih.gov/pubmed/19123797},
Abstract = {A polymer brush consisting of 70\% poly(N-isopropylacrylamide)
(PNIPAAM) and 30\% polymethacrylic acid (PMAA) was
synthesized from gold substrates with a "grafting from"
AIBN-type free-radical initiator. Fractionation of two
peptides, bradykinin and buccalin, was accomplished in less
than 120 s by placing a 30 pM (pH similar to 6.2) droplet
onto the polymer brush substrate. The eluant containing the
anionic buccalin is pipetted away for MALDI analysis while
the cationic bradykinin adsorbed to the swollen anionic
brush and was subsequently released by adding a droplet of
formic acid to the substrate. This caused the brush to
collapse and release the bradykinin, much like squeezing a
sponge; these nanosponge substrates exhibited very high
loading capacity ($>$2.0 mg/mL compared to
plasma-polymer-modified MALDI substrates. Ellipsometric
measurements showed that complementary peptides adsorb
rapidly while those of the same charge do not, and MALDI-MS
analysis of the two fractions showed separation of both
peptides. The adsorption of bradykinin was monitored over
time, and 85\% of the peptide had been adsorbed to the
nanosponge in 1 min from a 0.5 mg/mL aqueous
solution.},
Doi = {10.1021/la802723r},
Key = {Wong09}
}
@article{fds263360,
Author = {Barthel, J and Konkar, S and Sankin, G and Darling, E and Guilak, F and Zhong, P and LaMattina, B and Zauscher, S},
Title = {Effect of shockwaves on the biomechanical and biochemical
function of cells},
Journal = {Society for Experimental Mechanics 11th International
Congress and Exhibition on Experimental and Applied
Mechanics 2008},
Volume = {3},
Pages = {1315-1319},
Year = {2008},
Month = {December},
Abstract = {The number of non-lethal cases of soldiers being exposed to
blasts from improvised explosive devices (IED) has increased
significantly over the last few years. Concurrently, the
number of soft tissue injuries, including traumatic brain
injuries (TBI) and heterotopic ossification (HO, i.e.,
abnormal formation of bone in soft tissue) have increased.
Little is known, however, about the molecular and cellular
level effects of high strain-rate loading of soft tissues.
Here we report on the instrumentation and procedures we have
developed to apply high strain-rate loading to cell-sheets
in vitro and we will discuss the biomechanical and
biochemical properties of cells that have been exposed to
high strain rate loading conditions. © 2008 Society for
Experimental Mechanics Inc.},
Key = {fds263360}
}
@booklet{Hook08,
Author = {Höök, F and Kasemo, B and Grunze, M and Zauscher,
S},
Title = {Quantitative biological surface science: challenges and
recent advances.},
Journal = {Acs Nano},
Volume = {2},
Number = {12},
Pages = {2428-2436},
Year = {2008},
Month = {December},
ISSN = {1936-0851},
url = {http://www.ncbi.nlm.nih.gov/pubmed/19206275},
Abstract = {Biological surface science is a broad, interdisciplinary
subfield of surface science, where properties and processes
at biological and synthetic surfaces and interfaces are
investigated, and where biofunctional surfaces are
fabricated. The need to study and to understand biological
surfaces and interfaces in liquid environments provides
sizable challenges as well as fascinating opportunities.
Here, we report on recent progress in biological surface
science that was described within the program assembled by
the Biomaterial Interface Division of the Science and
Technology of Materials, Interfaces and Processes
(www.avs.org) during their 55th International Symposium and
Exhibition held in Boston, October 19-24, 2008. The selected
examples show that the rapid progress in nanoscience and
nanotechnology, hand-in-hand with theory and simulation,
provides increasingly sophisticated methods and tools to
unravel the mechanisms and details of complex processes at
biological surfaces and in-depth understanding of
biomolecular surface interactions.},
Doi = {10.1021/nn800800v},
Key = {Hook08}
}
@booklet{Mock08,
Author = {Mock, JJ and Hill, RT and Degiron, A and Zauscher, S and Chilkoti, A and Smith, DR},
Title = {Distance-dependent plasmon resonant coupling between a gold
nanoparticle and gold film.},
Journal = {Nano Letters},
Volume = {8},
Number = {8},
Pages = {2245-2252},
Year = {2008},
Month = {August},
ISSN = {1530-6984},
url = {http://www.ncbi.nlm.nih.gov/pubmed/18590340},
Abstract = {We present an experimental analysis of the plasmonic
scattering properties of gold nanoparticles controllably
placed nanometers away from a gold metal film. We show that
the spectral response of this system results from the
interplay between the localized plasmon resonance of the
nanoparticle and the surface plasmon polaritons of the gold
film, as previously predicted by theoretical studies. In
addition, we report that the metal film induces a
polarization to the single nanoparticle light scattering,
resulting in a doughnut-shaped point spread function when
imaged in the far-field. Both the spectral response and the
polarization effects are highly sensitive to the
nanoparticle-film separation distance. Such a system shows
promise in potential biometrology and diagnostic
devices.},
Doi = {10.1021/nl080872f},
Key = {Mock08}
}
@booklet{Valiaev08,
Author = {Valiaev, A and Lim, DW and Schmidler, S and Clark, RL and Chilkoti, A and Zauscher, S},
Title = {Hydration and conformational mechanics of single,
end-tethered elastin-like polypeptides.},
Journal = {Journal of the American Chemical Society},
Volume = {130},
Number = {33},
Pages = {10939-10946},
Year = {2008},
Month = {August},
ISSN = {0002-7863},
url = {http://www.ncbi.nlm.nih.gov/pubmed/18646848},
Abstract = {We investigated the effect of temperature, ionic strength,
solvent polarity, and type of guest residue on the
force-extension behavior of single, end-tethered
elastin-like polypeptides (ELPs), using single molecule
force spectroscopy (SMFS). ELPs are stimulus-responsive
polypeptides that contain repeats of the five amino acids
Val-Pro-Gly-Xaa-Gly (VPGXG), where Xaa is a guest residue
that can be any amino acid with the exception of proline. We
fitted the force-extension data with a freely jointed chain
(FJC) model which allowed us to resolve small differences in
the effective Kuhn segment length distributions that largely
arise from differences in the hydrophobic hydration behavior
of ELP. Our results agree qualitatively with predictions
from recent molecular dynamics simulations and demonstrate
that hydrophobic hydration modulates the molecular
elasticity for ELPs. Furthermore, our results show that
SMFS, when combined with our approach for data analysis, can
be used to study the subtleties of polypeptide-water
interactions and thus provides a basis for the study of
hydrophobic hydration in intrinsically unstructured
biomacromolecules.},
Doi = {10.1021/ja800502h},
Key = {Valiaev08}
}
@booklet{Singamaneni08,
Author = {Singamaneni, S and LeMieux, MC and Lang, HP and Gerber, C and Lam, Y and Zauscher, S and Datskos, PG and Lavrik, NV and Jiang, H and Naik, RR and Bunning, TJ and Tsukruk, VV},
Title = {Bimaterial microcantilevers as a hybrid sensing
platform},
Journal = {Advanced Materials (Deerfield Beach, Fla.)},
Volume = {20},
Number = {4},
Pages = {653-680},
Publisher = {WILEY},
Year = {2008},
Month = {February},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.200701667},
Abstract = {Microcantilevers, one of the most common MEMS structures,
have been introduced as a novel sensing paradigm nearly a
decade ago. Ever since, the technology has emerged to find
important applications in chemical, biological and physical
sensing areas. Today the technology stands at the verge of
providing the next generation of sophisticated sensors (such
as artificial nose, artificial tongue) with extremely high
sensitivity and miniature size. The article provides an
overview of the modes of detection, theory behind the
transduction mechanisms, materials employed as active
layers, and some of the important applications. Emphasizing
the material design aspects, the review underscores the most
important findings, current trends, key challenges and
future directions of the microcantilever based sensor
technology. © 2008 WILEY-VCH Verlag GmbH & Co.
KGaA.},
Doi = {10.1002/adma.200701667},
Key = {Singamaneni08}
}
@booklet{Chang08,
Author = {Chang, DP and Abu-Lail, NI and Guilak, F and Jay, GD and Zauscher,
S},
Title = {Conformational mechanics, adsorption, and normal force
interactions of lubricin and hyaluronic acid on model
surfaces.},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {24},
Number = {4},
Pages = {1183-1193},
Year = {2008},
Month = {February},
ISSN = {0743-7463},
url = {http://www.ncbi.nlm.nih.gov/pubmed/18181652},
Abstract = {Glycoproteins, such as lubricin, and hyaluronic acid (HA)
play a prominent role in the boundary lubrication mechanism
in diarthrodial joints. Although many studies have tried to
elucidate the lubrication mechanisms of articular cartilage,
the molecular details of how lubricin and HA interact with
cartilage surfaces and mediate their interaction still
remain poorly understood. Here we used model substrates,
functionalized with self-assembled monolayers terminating in
hydroxyl or methyl groups, (1) to determine the effect of
surface chemistry on lubricin and HA adsorption using
surface plasmon resonance (SPR) and (2) to study normal
force interactions between these surfaces as a function of
lubricin and HA concentration using colloidal probe
microscopy. We found that lubricin is amphiphilic and
adsorbed strongly onto both methyl- and hydroxyl-terminated
surfaces. On hydrophobic surfaces, lubricin likely adopts a
compact, looplike conformation in which its hydrophobic
domains at the N and C termini serve as surface anchors. On
hydrophilic surfaces, lubricin likely adsorbs anywhere along
its hydrophilic central domain and adopts, with increasing
solution concentration, an extended tail-like conformation.
Overall, lubricin develops strong repulsive interactions
when compressing two surfaces into contact. Furthermore,
upon surface separation, adhesion occurs between the
surfaces as a result of molecular bridging and chain
disentanglement. This behavior is in contrast to that of HA,
which does not adsorb appreciably on either of the model
surfaces and does not develop significant repulsive
interactions. Adhesive forces, particularly between the
hydrophobic surfaces, are large and not appreciably affected
by HA. For a mixture of lubricin and HA, we observed
slightly larger adsorptions and repulsions than those found
for lubricin alone. Our experiments suggest that this
interaction depends on unspecific physical rather than
chemical interactions between lubricin and HA. We speculate
that in mediating interactions at the cartilage surface, an
important role of lubricin, possibly in conjunction with HA,
is one of providing a protective coating on cartilage
surfaces that maintains the contacting surfaces in a
sterically repulsive state.},
Doi = {10.1021/la702366t},
Key = {Chang08}
}
@booklet{Coles08,
Author = {Coles, JM and Blum, JJ and Jay, GD and Darling, EM and Guilak, F and Zauscher, S},
Title = {In situ friction measurement on murine cartilage by atomic
force microscopy.},
Journal = {Journal of Biomechanics},
Volume = {41},
Number = {3},
Pages = {541-548},
Year = {2008},
Month = {January},
ISSN = {0021-9290},
url = {http://www.ncbi.nlm.nih.gov/pubmed/18054362},
Abstract = {Articular cartilage provides a low-friction, wear-resistant
surface for the motion of diarthrodial joints. The objective
of this study was to develop a method for in situ friction
measurement of murine cartilage using a colloidal probe
attached to the cantilever of an atomic force microscope.
Sliding friction was measured between a chemically
functionalized microsphere and the cartilage of the murine
femoral head. Friction was measured at normal loads ranging
incrementally from 20 to 100 nN with a sliding speed of 40
microm/s and sliding distance of 64 microm. Under these test
conditions, hydrostatic pressurization and biphasic load
support in the cartilage were minimized, providing
frictional measurements that predominantly reflect boundary
lubrication properties. Friction coefficients measured on
murine tissue (0.25+/-0.11) were similar to those measured
on porcine tissue (0.23+/-0.09) and were in general
agreement with measurements of boundary friction on
cartilage by other researchers. Using the colloidal probe as
an indenter, the elastic mechanical properties and surface
roughness were measured in the same configuration.
Interfacial shear was found to be the principal mechanism of
friction generation, with little to no friction resulting
from plowing forces, collision forces, or energy losses due
to normal deformation. This measurement technique can be
applied to future studies of cartilage friction and
mechanical properties on genetically altered mice or other
small animals.},
Doi = {10.1016/j.jbiomech.2007.10.013},
Key = {Coles08}
}
@booklet{Darling08,
Author = {Darling, EM and Topel, M and Zauscher, S and Vail, TP and Guilak,
F},
Title = {Viscoelastic properties of human mesenchymally-derived stem
cells and primary osteoblasts, chondrocytes, and
adipocytes.},
Journal = {Journal of Biomechanics},
Volume = {41},
Number = {2},
Pages = {454-464},
Year = {2008},
Month = {January},
ISSN = {0021-9290},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17825308},
Abstract = {The mechanical properties of single cells play important
roles in regulating cell-matrix interactions, potentially
influencing the process of mechanotransduction. Recent
studies also suggest that cellular mechanical properties may
provide novel biological markers, or "biomarkers," of cell
phenotype, reflecting specific changes that occur with
disease, differentiation, or cellular transformation. Of
particular interest in recent years has been the
identification of such biomarkers that can be used to
determine specific phenotypic characteristics of stem cells
that separate them from primary, differentiated cells. The
goal of this study was to determine the elastic and
viscoelastic properties of three primary cell types of
mesenchymal lineage (chondrocytes, osteoblasts, and
adipocytes) and to test the hypothesis that primary
differentiated cells exhibit distinct mechanical properties
compared to adult stem cells (adipose-derived or bone
marrow-derived mesenchymal stem cells). In an adherent,
spread configuration, chondrocytes, osteoblasts, and
adipocytes all exhibited significantly different mechanical
properties, with osteoblasts being stiffer than chondrocytes
and both being stiffer than adipocytes. Adipose-derived and
mesenchymal stem cells exhibited similar properties to each
other, but were mechanically distinct from primary cells,
particularly when comparing a ratio of elastic to relaxed
moduli. These findings will help more accurately model the
cellular mechanical environment in mesenchymal tissues,
which could assist in describing injury thresholds and
disease progression or even determining the influence of
mechanical loading for tissue engineering efforts.
Furthermore, the identification of mechanical properties
distinct to stem cells could result in more successful
sorting procedures to enrich multipotent progenitor cell
populations.},
Doi = {10.1016/j.jbiomech.2007.06.019},
Key = {Darling08}
}
@booklet{Ducker08,
Author = {Ducker, R and Garcia, A and Zhang, JM and Chen, T and Zauscher,
S},
Title = {Polymeric and biomacromolecular brush nanostructures:
progress in synthesis, patterning and characterization},
Journal = {Soft Matter},
Volume = {4},
Number = {9},
Pages = {1774-1786},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2008},
ISSN = {1744-683X},
url = {http://dx.doi.org/10.1039/b804861b},
Abstract = {A significant scientific and engineering challenge of recent
years has been the fabrication of patterned polymeric and
biomacromolecular brush nanostructures on surfaces. These
structures provide researchers with a rich platform on which
to exploit and observe nanoscale phenomena. In this review
we present an overview of the field and highlight, through
selected examples, recent advances in the nanostructuring of
polymer and biomacromolecular brushes. This includes a brief
overview of polymer brush synthesis techniques and how these
are integrated with nanolithographic and templating
approaches. We discuss the characterization of polymeric
nanostructures and its associated difficulties, and we
provide some perspective of how we see the future direction
of the field evolving.},
Doi = {10.1039/b804861b},
Key = {Ducker08}
}
@booklet{Zhang08,
Author = {Zhang, JM and Nylander, T and Campbell, RA and Rennie, AR and Zauscher,
S and Linse, P},
Title = {Novel evaluation method of neutron reflectivity data applied
to stimulus-responsive polymer brushes},
Journal = {Soft Matter},
Volume = {4},
Number = {3},
Pages = {500-509},
Publisher = {Royal Society of Chemistry (RSC)},
Year = {2008},
ISSN = {1744-683X},
url = {http://dx.doi.org/10.1039/b714911e},
Abstract = {Neutron reflectivity (NR) measurements have been performed
on stimulus-responsive polymer brushes containing
N-isopropylacrylamide (NIPAAM) at different temperatures and
contrasts using two different brush samples of roughly the
same grafting density and layer thickness. The NR data were
analyzed using a novel method employing polymer density
profiles predicted from lattice mean-field theory augmented
with a polymer model to describe polymer solubility that
decreases with increasing temperature. The predicted density
profiles at the different temperatures were self-consistent
with the experimentally observed profiles; hence the
experimental data lend credibility to the theory. We found
that the brush thickness decreased from 220 to 160 nm and
the polymer volume fraction increased from 55 to 75\% when
increasing temperature from 293 to 328 K. The new evaluation
approach involved significantly fewer independent fitting
parameters than methods involving layers of uniform
densities. Furthermore, the approach can straightforwardly
be extended to analyze neutron reflectivity data of grafted,
weakly charged polymers that display pH-sensitive behaviour
and also to block copolymers and to surfaces with adsorbed
polymers. We propose that such accurate model calculations
provide a tool to interpret results from NR experiments more
effectively and design neutron reflectivity experiments for
optimal outcome.},
Doi = {10.1039/b714911e},
Key = {Zhang08}
}
@article{fds263367,
Author = {Lam, Y and Valiaev, A and Lim, DW and Chilkoti, A and Alam, SM and Zauscher, S},
Title = {Single molecule nanomechanics of HIV-1 envelope
glycoproteins and elastin-like polypeptides},
Journal = {Proceedings of the Sem Annual Conference and Exposition on
Experimental and Applied Mechanics 2007},
Volume = {1},
Pages = {624-625},
Year = {2007},
Month = {November},
Key = {fds263367}
}
@article{fds319139,
Author = {Garcia, A and Hucknall, A and Johannes, M and Clark, R and Chilkoti, A and Zauscher, S},
Title = {POLY 627-Fabrication of bioconjugated and hybrid polymeric
nanostructures by field-induced scanning probe
lithography},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {234},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2007},
Month = {August},
Key = {fds319139}
}
@booklet{Valiaev07,
Author = {Valiaev, A and Lim, DW and Oas, TG and Chilkoti, A and Zauscher,
S},
Title = {Force-induced prolyl cis-trans isomerization in elastin-like
polypeptides.},
Journal = {Journal of the American Chemical Society},
Volume = {129},
Number = {20},
Pages = {6491-6497},
Year = {2007},
Month = {May},
ISSN = {0002-7863},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17469821},
Abstract = {Elastin-like polypeptides (ELPs) are stimulus-responsive
polymers that contain repeats of five amino acids,
Val-Pro-Gly-Xaa-Gly (VPGXG), where Xaa is a guest residue
that can be any amino acid with the exception of proline.
While studying the conformational mechanics of ELPs over a
range of solvent conditions by single-molecule force
spectroscopy, we noticed that some force-extension curves
showed temperature-independent, extensional transitions that
could not be fitted with a freely jointed chain or worm-like
chain model. Here we show that the observed molecular
elongation results from the force-induced peptidyl-prolyl
cis-trans isomerization in prolines, which are repeated
every fifth residue in the main chain of ELPs. Control
experiments with poly(L-proline) demonstrate the similarity
of the conformational transition between poly(L-proline) and
ELPs. In contrast, the force-extension behavior of
poly(L-lysine) showed no deviation in the relevant force
range. Force-extension curves in hysteresis experiments
showed an elongational difference between extension and
relaxation pathways that suggests that the cis
conformational state of the prolines could be exhausted on
the time scale of the experiment. We present further
computational evidence for this mechanism by Monte Carlo
simulation of the force-extension behavior using an
elastically coupled, two-state model. We believe ours is the
first demonstration of force-induced prolyl cis-trans
isomerization in proline-containing polypeptides. Our
results suggest that single-molecule force spectroscopy
could provide an alternate means to assay this important
conformational transition in polypeptides.},
Doi = {10.1021/ja070147r},
Key = {Valiaev07}
}
@booklet{Darling07,
Author = {Darling, EM and Zauscher, S and Block, JA and Guilak,
F},
Title = {A thin-layer model for viscoelastic, stress-relaxation
testing of cells using atomic force microscopy: do cell
properties reflect metastatic potential?},
Journal = {Biophysical Journal},
Volume = {92},
Number = {5},
Pages = {1784-1791},
Year = {2007},
Month = {March},
ISSN = {0006-3495},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17158567},
Abstract = {Atomic force microscopy has rapidly become a valuable tool
for quantifying the biophysical properties of single cells.
The interpretation of atomic force microscopy-based
indentation tests, however, is highly dependent on the use
of an appropriate theoretical model of the testing
configuration. In this study, a novel, thin-layer
viscoelastic model for stress relaxation was developed to
quantify the mechanical properties of chondrosarcoma cells
in different configurations to examine the hypothesis that
viscoelastic properties reflect the metastatic potential and
invasiveness of the cell using three well-characterized
human chondrosarcoma cell lines (JJ012, FS090, 105KC) that
show increasing chondrocytic differentiation and decreasing
malignancy, respectively. Single-cell stress relaxation
tests were conducted at 2 h and 2 days after plating to
determine cell mechanical properties in either spherical or
spread morphologies and analyzed using the new theoretical
model. At both time points, JJ012 cells had the lowest
moduli of the cell lines examined, whereas FS090 typically
had the highest. At 2 days, all cells showed an increase in
stiffness and a decrease in apparent viscosity compared to
the 2-h time point. Fluorescent labeling showed that the
F-actin structure in spread cells was significantly
different between FS090 cells and JJ012/105KC cells. Taken
together with results of previous studies, these findings
indicate that cell transformation and tumorigenicity are
associated with a decrease in cell modulus and apparent
viscosity, suggesting that cell mechanical properties may
provide insight into the metastatic potential and
invasiveness of a cell.},
Doi = {10.1529/biophysj.106.083097},
Key = {Darling07}
}
@booklet{Lee07,
Author = {W. K. Lee and S. H. Chen and A. Chilkoti and S.
Zauscher},
Title = {Fabrication of gold nanowires by electric-field-induced
scanning probe lithography and in situ chemical
development},
Journal = {Small},
Volume = {3},
Number = {2},
Pages = {249 -- 254},
Year = {2007},
Month = {February},
ISSN = {1613-6810},
Key = {Lee07}
}
@article{070810435270,
Author = {Lee, W-K and Chen, S and Chilkoti, A and Zauscher,
S},
Title = {Fabrication of gold nanowires by electric-field-induced
scanning probe lithography and in situ chemical
development.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {3},
Number = {2},
Pages = {249-254},
Year = {2007},
Month = {February},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17199247},
Keywords = {Biosensors;Electric field effects;Gold;Lithography;Surface
plasmon resonance;},
Abstract = {A new approach to fabricate surface-confined gold
nanostructures by electric-field-induced scanning probe
lithography (SPL) for electronic and plasmonic applications,
which enables precise control over the feature dimension and
position at the nanometer-length scale, is discussed. The
approach promises massively parallel implementation through
an anodization stamping process and has potential for the
fabrication of nanoelectronic devices, biosensors, and
surface plasmonic sensors. Clusters of gold atoms are
concomitantly deposited during the patterning of
SiO<sub>2</sub> nanostructures by the SPL. Other metallic
nanowires can be fabricated by using gold seeds and an
appropriately matched developing route, which suggests that
different functional nanowires can also be fabricated. This
approach has potential for the fabrication of nanoelectronic
devices, biosensors, and surface plasmonic
sensors.},
Doi = {10.1002/smll.200600396},
Key = {070810435270}
}
@booklet{Chang07,
Author = {D. P. Chang and J. E. Dolbow and S. Zauscher},
Title = {Switchable friction of stimulus-responsive
hydrogels},
Journal = {Langmuir},
Volume = {23},
Number = {1},
Pages = {250 -- 257},
Year = {2007},
Month = {January},
ISSN = {0743-7463},
Abstract = {Poly(N-isopropylacrylamide) (pNIPAAm) gels are
stimulus-responsive hydrogels that exhibit large reversible
changes in their volume and surface physicochemical
properties near the lower critical solution temperature
(LCST) in response to external stimuli, such as a change in
temperature or solvent composition. Here we report how
different phase states, induced isothermally by changes in
the solvent composition, affect the tribological properties
of pNIPAAm hydrogels. Our measurements indicate that gels in
a collapsed conformation (above the LCST) exhibit
significantly more friction than swollen gels (below the
LCST) at low shear rates. These differences arise from
changes in the surface roughness, adhesive interactions, and
chain entanglements of the gel surfaces associated with the
phase transition. Importantly, we show that the changes in
friction, triggered by an external stimulus, are reversible.
These reversible and possibly tunable changes in friction
may have a significant impact on the design of coatings for
biosensors and for actuation devices based on
stimulus-responsive hydrogels.},
Key = {Chang07}
}
@booklet{Lee07a,
Author = {W. K. Lee and M. Patra and P. Linse and S.
Zauscher},
Title = {Scaling behavior of nanopatterned polymer
brushes},
Journal = {Small},
Volume = {3},
Number = {1},
Pages = {63 -- 66},
Year = {2007},
Month = {January},
ISSN = {1613-6810},
Key = {Lee07a}
}
@booklet{Valiaev07a,
Author = {A. Valiaev and N. I. Abu-lail and D. W. Lim and A. Chilkoti and S. Zauscher},
Title = {Microcantilever sensing and actuation with end-grafted
stimulus-responsive elastin-like polypeptides},
Journal = {Langmuir},
Volume = {23},
Number = {1},
Pages = {339 -- 344},
Year = {2007},
Month = {January},
ISSN = {0743-7463},
Abstract = {Stimulus-responsive elastin-like polypeptides (ELPs) grafted
onto surfaces are of significant technical interest because
they can be exploited for force generation, in sensing
applications, or as molecular switches with tunable
properties. Changes in the conformational state of grafted
ELPs, induced by a phase transition or changes in osmotic
pressure, lead to significant changes in the surface stress
in the ELP graft layer and translate into detectable changes
in microcantilever deflection. In this study, we investigate
the conformational mechanics of ELPs in response to changes
in solution pH and ionic strength using atomic force
microscopy (AFM) microcantilever deflection and quartz
crystal microbalance (QCM) measurements. We show that the
use of genetically encoded, surface-grafted ELPs is exciting
for cantilever actuation and sensing because commonly
available microfabricated cantilever springs offer a simple
and nonintrusive way to detect changes in solvent type,
temperature, and pH, promising great potential for sensing
applications in microfluidic devices.},
Key = {Valiaev07a}
}
@booklet{Lam07,
Author = {Lam, Y and Alam, MS and Zauscher, S},
Title = {Molecular-recognition force spectroscopy of induced-fit
antibody binding to HIV-1 env gp120 and a nano-mechanical
approach to understanding neutralizing antibody unbinding
behavior},
Journal = {Biophysical Journal},
Pages = {514A-514A},
Publisher = {BIOPHYSICAL SOCIETY},
Year = {2007},
Month = {January},
ISSN = {0006-3495},
url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000243972403254&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92},
Key = {Lam07}
}
@article{070410390784,
Author = {Chang, DP and Dolbow, JE and Zauscher, S},
Title = {Switchable friction of stimulus-responsive
hydrogels.},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {23},
Number = {1},
Pages = {250-257},
Year = {2007},
Month = {January},
ISSN = {0743-7463},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17190511},
Keywords = {Adhesives;Biosensors;Coatings;Phase transitions;Physical
chemistry;Solvents;Surface roughness;},
Abstract = {Poly(N-isopropylacrylamide) (pNIPAAm) gels are
stimulus-responsive hydrogels that exhibit large reversible
changes in their volume and surface physicochemical
properties near the lower critical solution temperature
(LCST) in response to external stimuli, such as a change in
temperature or solvent composition. Here we report how
different phase states, induced isothermally by changes in
the solvent composition, affect the tribological properties
of pNIPAAm hydrogels. Our measurements indicate that gels in
a collapsed conformation (above the LCST) exhibit
significantly more friction than swollen gels (below the
LCST) at low shear rates. These differences arise from
changes in the surface roughness, adhesive interactions, and
chain entanglements of the gel surfaces associated with the
phase transition. Importantly, we show that the changes in
friction, triggered by an external stimulus, are reversible.
These reversible and possibly tunable changes in friction
may have a significant impact on the design of coatings for
biosensors and for actuation devices based on
stimulus-responsive hydrogels.},
Doi = {10.1021/la0617006},
Key = {070410390784}
}
@article{070410390786,
Author = {Valiaev, A and Abu-Lail, NI and Lim, DW and Chilkoti, A and Zauscher,
S},
Title = {Microcantilever sensing and actuation with end-grafted
stimulus-responsive elastin-like polypeptides.},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {23},
Number = {1},
Pages = {339-344},
Year = {2007},
Month = {January},
ISSN = {0743-7463},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17190524},
Keywords = {Atomic force microscopy;Graft copolymers;Phase
transitions;Quartz;pH effects;},
Abstract = {Stimulus-responsive elastin-like polypeptides (ELPs) grafted
onto surfaces are of significant technical interest because
they can be exploited for force generation, in sensing
applications, or as molecular switches with tunable
properties. Changes in the conformational state of grafted
ELPs, induced by a phase transition or changes in osmotic
pressure, lead to significant changes in the surface stress
in the ELP graft layer and translate into detectable changes
in microcantilever deflection. In this study, we investigate
the conformational mechanics of ELPs in response to changes
in solution pH and ionic strength using atomic force
microscopy (AFM) microcantilever deflection and quartz
crystal microbalance (QCM) measurements. We show that the
use of genetically encoded, surface-grafted ELPs is exciting
for cantilever actuation and sensing because commonly
available microfabricated cantilever springs offer a simple
and nonintrusive way to detect changes in solvent type,
temperature, and pH, promising great potential for sensing
applications in microfluidic devices.},
Doi = {10.1021/la0616698},
Key = {070410390786}
}
@article{070410384139,
Author = {Lee, W-K and Patra, M and Linse, P and Zauscher, S},
Title = {Scaling behavior of nanopatterned polymer
brushes.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {3},
Number = {1},
Pages = {63-66},
Year = {2007},
Month = {January},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17294470},
Keywords = {Atomic force microscopy;Computer simulation;Grain
boundaries;Molecular dynamics;Molecular weight;Organic
polymers;Pattern recognition;},
Abstract = {The scaling behavior of poly(N-isopropyacrylamide) (pNIPAAM)
polymer brushes was investigated. The brush height of
different footprint sizes, polymer molecular weights and
surface-grafting densities was analyzed using scaling
relations obtained from coarse grained model. Molecular
dynamics simulation method was used for development of
scaling relation of brush height in terms of features widths
at various chain lengths and grafting densities. The
theoretical prediction was validated by comparing the
predicted scaling behavior of the brush height with that
obtained from height measurements on nano- and
micropatterned pNIPAAM polymer brushed. It was observed that
polymer heights measured in dry states vary as function of
patterned feature width for various reaction time and
polymer height increases at small feature width. Result
shows that scaling prediction provide a useful tool for the
design and fabrication of polymeric and bio-macromolecular
nanostructures on surfaces.},
Doi = {10.1002/smll.200600414},
Key = {070410384139}
}
@article{065010304059,
Author = {Lam, Y and Abu-Lail, NI and Alam, MS and Zauscher,
S},
Title = {Using microcantilever deflection to detect HIV-1 envelope
glycoprotein gp120.},
Journal = {Nanomedicine},
Volume = {2},
Number = {4},
Pages = {222-229},
Year = {2006},
Month = {December},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17292147},
Keywords = {Monoclonal antibodies;Viruses;Glycols;Solutions;Molecular
biology;Binding energy;Biosensors;},
Abstract = {Microcantilevers have been used over the last decade to
detect biomolecules from solution. Specific binding events
on one surface of the microcantilever create a differential
stress, resulting in measurable deflection. Here we use this
principle to detect human immunodeficiency virus type 1
(HIV-1) envelope glycoprotein (Env) gp120 from solution. We
observed deflections approximately twice that of the
baseline (in PBS) upon specific binding of gp120 to
cantilevers decorated on one side with monoclonal antibodies
(mAbs) A32 or T8. Subsequent incubation with mAb 17b (known
to bind an A32-induced epitope on gp120) further increased
deflection of A32- but not T8-presenting cantilevers. This
work shows the capability of microcantilever deflection
sensors to detect an induced-fit interaction at test
concentrations of 8 microg/mL gp120 and 0.17 mg/mL 17b.
Further development of this technique could lead to a
portable, low-cost device for the effective detection of
HIV-1.},
Doi = {10.1016/j.nano.2006.10.002},
Key = {065010304059}
}
@article{065010301595,
Author = {Loveless, DM and Abu-Lail, NI and Kaholek, M and Zauscher, S and Craig,
SL},
Title = {Reversibly cross-linked surface-grafted polymer
brushes.},
Journal = {Angewandte Chemie International Edition},
Volume = {45},
Number = {46},
Pages = {7812-7814},
Year = {2006},
Month = {November},
ISSN = {1433-7851},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17066386},
Keywords = {Crosslinking;Thin films;Reaction kinetics;Supramolecular
chemistry;Surface chemistry;},
Abstract = {Detailed brush work: Structurally and thermodynamically
similar cross-linkers have opposite effects on the lateral
resistance of grafted thin films of poly(4-vinylpyridine)
brushes. The chemically reversible changes in mechanics are
influenced by the dissimilar kinetics of the cross-linking
interaction. (Figure Presented). © 2006 Wiley-VCH
Verlag GmbH and Co. KGaA.},
Doi = {10.1002/anie.200602508},
Key = {065010301595}
}
@article{fds319140,
Author = {Chang, DP and Dolbow, JE and Zauscher, S},
Title = {POLY 101-Switchable friction of stimulus-responsive
hydrogels},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {232},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2006},
Month = {September},
Key = {fds319140}
}
@article{063610102645,
Author = {Kaholek, M and Lee, WK and Feng, J and Lamattina, B and Dyer, DJ and Zauscher, S},
Title = {Weak polyelectrolyte brush arrays fabricated by combining
electron-beam lithography with surface-initiated
photopolymerization},
Journal = {Chemistry of Materials},
Volume = {18},
Number = {16},
Pages = {3660-3664},
Publisher = {American Chemical Society (ACS)},
Year = {2006},
Month = {August},
ISSN = {0897-4756},
url = {http://dx.doi.org/10.1021/cm060276r},
Keywords = {Polyelectrolytes;Electron beam lithography;Photopolymerization;pH
effects;Salts;Ultraviolet radiation;Free radical
polymerization;Initiators (chemical);Ionic
strength;},
Abstract = {We present a simple "top-down/bottom-up" strategy to
fabricate nano- and micropatterned polymer brush arrays
composed of pH- and salt-sensitive, weak polyelectrolyte
copolymers [poly(N-isopropy-lacrylamide-co- methacrylic
acid, 3:1, poly (NIPAAM-co-MAA)]. In our approach, a silicon
surface is first patterned with gold, using "lift-off'
electron-beam lithography ("top-down"), and the resulting
pattern is then amplified by surface-initiated
photopolymerization by conventional, UV-light-induced free
radical polymerization ("bottom-up") from an immobilized
2,2′-azobisisobutyronitrile (AIBN) type initiator. The use
of pH- and ionic-strength-sensitive comonomers in the
copolymer brush enables large, externally triggered
conformational changes of the micro- and nanopatterned
polymer brushes. We observed that the height of
nanopatterned ionized polymer brushes increases with
increasing feature size of the pattern. The design and
fabrication of surfaces with conformationally switchable,
patterned polymeric structures is important for sensing and
actuation applications on the micro- and nanoscales. © 2006
American Chemical Society.},
Doi = {10.1021/cm060276r},
Key = {063610102645}
}
@article{fds263359,
Author = {Abu-Lail, N and Jay, GD and Coles, J and Guilak, F and Zauscher,
S},
Title = {Friction reducing properties of lubricin (PRG4): A nanoscale
study of chondroprotection},
Journal = {European Cells and Materials},
Volume = {12},
Number = {SUPPL.1},
Pages = {48},
Year = {2006},
Month = {August},
ISSN = {1473-2262},
Key = {fds263359}
}
@article{fds263352,
Author = {Kenan, DJ and Walsh, EB and Meyers, SR and O'Toole, GA and Carruthers,
EG and Lee, WK and Zauscher, S and Prata, CAH and Grinstaff,
MW},
Title = {Peptide-PEG amphiphiles as cytophobic coatings for mammalian
and bacterial cells.},
Journal = {Chemistry & Biology},
Volume = {13},
Number = {7},
Pages = {695-700},
Year = {2006},
Month = {July},
ISSN = {1074-5521},
url = {http://www.ncbi.nlm.nih.gov/pubmed/16873017},
Abstract = {Amphiphilic macromolecules containing a polystyrene-adherent
peptide domain and a cell-repellent poly(ethylene glycol)
domain were designed, synthesized, and evaluated as a
cytophobic surface coating. Such cytophobic, or
cell-repellent, coatings are of interest for varied medical
and biotechnological applications. The composition of the
polystyrene binding peptide domain was identified using an
M13 phage display library. ELISA and atomic force
spectroscopy were used to evaluate the binding affinity of
the amphiphile peptide domain to polystyrene. When coated
onto polystyrene, the amphiphile reduced cell adhesion of
two distinct mammalian cell lines and pathogenic
Staphylococcus aureus strains.},
Doi = {10.1016/j.chembiol.2006.06.013},
Key = {fds263352}
}
@article{06259950330,
Author = {Lee, W-K and Caster, KC and Kim, J and Zauscher, S},
Title = {Nanopatterned polymer brushes by combining AFM anodization
lithography with ring-opening metathesis polymerization in
the liquid and vapor phase.},
Journal = {Small (Weinheim an Der Bergstrasse, Germany)},
Volume = {2},
Number = {7},
Pages = {848-853},
Year = {2006},
Month = {July},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17193132},
Keywords = {Nanostructured materials;Polymers;Ring opening
polymerization;Atomic force microscopy;Anodic
oxidation;Catalysts;},
Abstract = {The fabrication of patterned polymeric nanostructures
enables the development of miniaturized sensing and
diagnostic applications. The atomic force microscopy (AFM)
anodization, a form of field-induces scanning probe
lithography (FISPL) offers a powerful means to nanopattern
semiconductor surfaces with silicon oxide features that can
be used for subsequent modification with Ru-based metathesis
catalysts. A prototypical method is developed to fabricate
nanopatterned polymers structures by combining AFM
anodization lithography on silicon substrates with
surface-initiated ROMP. EFM phase imaging was used to
characterize the electronic state of the resulting
nanopatterned polymer structures. Nanopatterns of two
chemically different polymers were fabricated on a single
substrate by a step-and-repeat patterning and polymerization
approach. This process provides a universal platform for
surface-initiated polymerization and means to fabricate
complex polymeric structures.},
Doi = {10.1002/smll.200500470},
Key = {06259950330}
}
@article{fds263358,
Author = {Darling, EM and Zauscher, S and Guilak, F},
Title = {Viscoelastic properties of zonal articular chondrocytes
measured by atomic force microscopy.},
Journal = {Osteoarthritis and Cartilage},
Volume = {14},
Number = {6},
Pages = {571-579},
Year = {2006},
Month = {June},
ISSN = {1063-4584},
url = {http://www.ncbi.nlm.nih.gov/pubmed/16478668},
Abstract = {<h4>Objective</h4>Articular chondrocytes respond to chemical
and mechanical signals depending on their zone of origin
with respect to distance from the tissue surface. However,
little is known of the zonal variations in cellular
mechanical properties in cartilage. The goal of this study
was to determine the zonal variations in the elastic and
viscoelastic properties of porcine chondrocytes using atomic
force microscopy (AFM), and to validate this method against
micropipette aspiration.<h4>Methods</h4>A theoretical
solution for stress relaxation of a viscoelastic,
incompressible, isotropic surface indented with a hard,
spherical indenter (5 microm diameter) was derived and fit
to experimental stress-relaxation data for AFM indentation
of chondrocytes isolated from the superficial or middle/deep
zones of cartilage.<h4>Results</h4>The instantaneous moduli
of chondrocytes were 0.55+/-0.23 kPa for superficial cells
(S) and 0.29+/-0.14 kPa for middle/deep cells (M/D)
(P<0.0001), and the relaxed moduli were 0.31+/-0.15 kPa (S)
and 0.17+/-0.09 kPa (M/D) (P<0.0001). The apparent
viscosities were 1.15+/-0.66 kPas (S) and 0.61+/-0.69 kPa-s
(M/D) (P<0.0001). Results from the micropipette aspiration
test showed similar cell moduli but higher apparent
viscosities, indicating that mechanical properties measured
by these two techniques are similar.<h4>Conclusion</h4>Our
findings suggest that chondrocyte biomechanical properties
differ significantly with the zone of origin, consistent
with previous studies showing zonal differences in
chondrocyte biosynthetic activity and gene expression. Given
the versatility and dynamic testing capabilities of AFM, the
ability to conduct stress-relaxation measurements using this
technique may provide further insight into the viscoelastic
properties of isolated cells.},
Doi = {10.1016/j.joca.2005.12.003},
Key = {fds263358}
}
@article{06249932007,
Author = {Jung, J and Kim, KW and Na, K and Kuholek, M and Zauscher, S and Hyun,
J},
Title = {Fabrication of micropatterned gold nanoparticle arrays as a
template for surface-initiated polymerization of
stimuli-responsive polymers},
Journal = {Macromolecular Rapid Communications},
Volume = {27},
Number = {10},
Pages = {776-780},
Publisher = {WILEY},
Year = {2006},
Month = {May},
ISSN = {1022-1336},
url = {http://dx.doi.org/10.1002/marc.200600069},
Keywords = {Gold;Polystyrenes;Polymerization;Silicon;Adsorption;},
Abstract = {This paper demonstrates a new, reliable, and simple method
for fabricating micropatterned nanoparticle arrays that can
serve as templates for the surface-initiated polymerization
of polymer brushes. As a proof of concept, we micropatterned
gold nanoparticles (Au-NPs, ≈10 nm) onto glass, silicon,
polystyrene, and gold surfaces by a simple three-step
process: (1) microcontact printing of soluble polymer, (2)
incubation with a solution of Au-NPs, and (3) lift-off of
the template in a mixture of ethanol and deionized water. 40
μm wide features were successfully fabricated without any
significant defects or nonspecific adsorption on the
background. To demonstrate the utility of these Au-NP
templates, we subsequently polymerized N-isopropylacry-lamide
by surface-initiated polymerization, using a surface-bound
initiator. © 2006 WILEY-VCH Verlag Gimbh & Co.
KGaA.},
Doi = {10.1002/marc.200600069},
Key = {06249932007}
}
@article{fds263362,
Author = {Abu-Lail, NI and Ohashi, T and Clark, RL and Erickson, HP and Zauscher,
S},
Title = {Understanding the elasticity of fibronectin fibrils:
unfolding strengths of FN-III and GFP domains measured by
single molecule force spectroscopy.},
Journal = {Matrix Biology : Journal of the International Society for
Matrix Biology},
Volume = {25},
Number = {3},
Pages = {175-184},
Year = {2006},
Month = {April},
ISSN = {0945-053X},
url = {http://www.ncbi.nlm.nih.gov/pubmed/16343877},
Abstract = {While it is well established that fibronectin (FN) matrix
fibrils are elastic, the mechanism of fibril elasticity
during extension is still debated. To investigate the
molecular origin of FN fibril elasticity, we used single
molecule force spectroscopy (SMFS) to determine the
unfolding behavior of a recombinant FN-III protein construct
that contained eight FN-III domains ((1-8)FN-III) and two
green fluorescent protein (GFP) domains. FN-III domains were
distinguished from GFP domains by their shorter unfolding
lengths. The unfolding strengths of both domains were
determined for a wide range of pulling rates (50 to 1,745
nm/s). We found that the mechanical stabilities of FN-III
and GFP domains were very similar to each other over the
entire range of pulling speeds. FN fibrils containing GFP
remain brightly fluorescent, even when stretched, meaning
that GFP domains remain largely folded. Since GFP and FN-III
have equal unfolding strengths, this suggests that FN-III
domains are not extensively unraveled in stretched FN
fibrils. Our results thus favor an alternative model, which
invokes a conformational change from a compact to an
extended conformation, as the basis for FN fibril
elasticity.},
Doi = {10.1016/j.matbio.2005.10.007},
Key = {fds263362}
}
@article{06099727804,
Author = {Abu-Lail, NI and Kaholek, M and LaMattina, B and Clark, RL and Zauscher,
S},
Title = {Micro-cantilevers with end-grafted stimulus-responsive
polymer brushes for actuation and sensing},
Journal = {Sensors and Actuators. B, Chemical},
Volume = {114},
Number = {1},
Pages = {371-378},
Publisher = {Elsevier BV},
Year = {2006},
Month = {March},
ISSN = {0925-4005},
url = {http://dx.doi.org/10.1016/j.snb.2005.06.003},
Keywords = {Sensors;Brushes;Copolymers;Macromolecules;Polymerization;Drug
products;Atomic force microscopy;Organic solvents;Fluidic
devices;Ionic strength;Phase transitions;Osmosis;Conformations;},
Abstract = {Stimulus-responsive macromolecules have attracted
significant interest due to their potential applications in
molecular motors, drug delivery, sensors, and actuation
devices. Poly(N-isopropylacrylamide) (pNIPAAM) alone or as a
copolymer is a stimulus-responsive polymer that undergoes an
inverse phase transition triggered by changes in the solvent
quality, such as temperature, ionic strength, pH, or
co-solvent concentration. Associated with this phase
transition is a significant conformational change. We show
that micro-cantilevers, decorated on one side with a pNIPAAM
brush or poly(N-isopropylacrylamide-co-N-vinylimidazole)
(pNIPAAM-VI) (7:3) brush, can be used to detect and
transduce this phase transition behavior. Changes in the
conformational state of the brush, induced by the phase
transition or changes in osmotic pressure, cause significant
changes in the surface stress in the brush that leads to
detectable changes in cantilever deflection. We show that
the use of pNIPAAM and its copolymers is exciting for
cantilever actuation and sensing because commonly available
micro-fabricated cantilever springs offer a simple and
non-intrusive way to detect changes in solvent type,
temperature, and pH, promising great potential for sensing
applications in micro-fluidic devices. © 2005 Elsevier B.V.
All rights reserved.},
Doi = {10.1016/j.snb.2005.06.003},
Key = {06099727804}
}
@article{fds319141,
Author = {Lee, W-K and Chen, S and Chilkoti, A and Zauscher,
S},
Title = {Fabrication of bioconjugated polymeric nanostructures and
metal nanowires by electric field-induced scanning probe
lithography},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {231},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2006},
Month = {March},
Key = {fds319141}
}
@article{fds319142,
Author = {Abu-Lail, N and Kaholek, M and Valiaev, A and Lim, D-W and Chilkoti, A and LaMattina, B and Clark, R and Zauscher, S},
Title = {Micro-cantilevers decorated with tethered
stimulus-responsive polymer brushes and polypeptides for
actuation and sensing},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {231},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2006},
Month = {March},
Key = {fds319142}
}
@article{06109738972,
Author = {Uner, B and Ramasubramanian, MK and Zauscher, S and Kadla,
JF},
Title = {Adhesion interactions between poly(vinyl alcohol) and
iron-oxide surfaces: The effect of acetylation},
Journal = {Journal of Applied Polymer Science},
Volume = {99},
Number = {6},
Pages = {3528-3534},
Publisher = {WILEY},
Year = {2006},
Month = {February},
ISSN = {0021-8995},
url = {http://dx.doi.org/10.1002/app.22980},
Keywords = {Polyvinyl alcohols;Iron oxides;Hydroxylation;Hydrogen
bonds;Fourier transform infrared spectroscopy;Atomic force
microscopy;},
Abstract = {Atomic force microscopy with chemically functionalized
colloidal probes was used to study "acid-base" interactions
between poly(vinyl alcohol) (PVA) and a metal surface. By
using well-defined model surfaces, we have studied the
adhesion forces between a hydroxylated surface and
cantilever tips with varying hydroxyl content. Decreasing
the amount of available hydroxyl groups dramatically reduced
the observed adhesion force. The calculated bond energy for
each cantilever tip was found to be in the range of typical
hydrogen bond energies, i.e., 10-40 kJ/mol, suggesting that
the acid-base interactions are pre dominately hydrogen
bonding. Similarly, the force versus distance curves using
PVA functionalized colloidal probes showed a strong
dependence on the chemical functionality of the tip and the
degree of acetylation of the intervening PVA. It was
observed that, with an increase in the acetyl content of the
PVA, the adhesion force decreased. © 2006 Wiley
Periodicals, Inc.},
Doi = {10.1002/app.22980},
Key = {06109738972}
}
@booklet{Loveless06,
Author = {D. M. Loveless and N. I. Abu-lail and M. Kaholek and S.
Zauscher and S. L. Craig},
Title = {Reversibly cross-linked surface-grafted polymer
brushes},
Journal = {Angewandte Chemie-international Edition},
Volume = {45},
Number = {46},
Pages = {7812 -- 7814},
Year = {2006},
ISSN = {1433-7851},
Key = {Loveless06}
}
@article{05509543649,
Author = {Bastidas, JC and Venditti, R and Pawlak, J and Gilbert, R and Zauscher,
S and Kadla, JF},
Title = {Chemical force microscopy of cellulosic fibers},
Journal = {Carbohydrate Polymers},
Volume = {62},
Number = {4},
Pages = {369-378},
Publisher = {Elsevier BV},
Year = {2005},
Month = {December},
ISSN = {0144-8617},
url = {http://dx.doi.org/10.1016/j.carbpol.2005.08.058},
Keywords = {Cellulose;Bleached pulp;Kraft pulp;pH effects;Surface
roughness;X ray photoelectron spectroscopy;Fourier transform
infrared spectroscopy;Atomic force microscopy;},
Abstract = {Atomic force microscopy with chemically modified cantilever
tips (chemical force microscopy) was used to study the
pull-off forces (adhesion forces) on cellulose model
surfaces and bleached softwood kraft pulp fibers in aqueous
media. It was found that for the -COOH terminated tips, the
adhesion forces are dependent on pH, whereas for the -CH3
and -OH terminated tips adhesion is not strongly affected by
pH. Comparison between the cellulose model surfaces and
cellulosic fibers under our experimental conditions reveal
that surface roughness does not affect adhesion strongly.
X-ray photoelectron spectroscopy (XPS) and Fourier
Transformed Infrared (FTIR) spectroscopy reveal that both
substrate surfaces have homogeneous chemical composition.
The results show that chemical force microscopy can be used
for the chemical characterization of cellulose surfaces at a
nano-level. © 2005 Elsevier Ltd. All rights
reserved.},
Doi = {10.1016/j.carbpol.2005.08.058},
Key = {05509543649}
}
@article{05439431733,
Author = {Chow, DC and Lee, W-K and Zauscher, S and Chilkoti,
A},
Title = {Enzymatic fabrication of DNA nanostructures: extension of a
self-assembled oligonucleotide monolayer on gold
arrays.},
Journal = {Journal of the American Chemical Society},
Volume = {127},
Number = {41},
Pages = {14122-14123},
Year = {2005},
Month = {October},
ISSN = {0002-7863},
url = {http://www.ncbi.nlm.nih.gov/pubmed/16218572},
Abstract = {Nucleic acid nanostructures are useful as templates for
bionanofabrication of composite molecular nanostructures in
materials science, molecular electronics, and biosensing.
Here, we demonstrate that terminal deoxynucleotidyl
transferase, which repetitively adds mononucleotides to the
3' end of a short DNA initiator, can be used to rapidly
fabricate DNA nanostructures up to 121 nm high with lateral
dimensions from 0.1 to 4 mum in 2 h. These programmable
scaffolds can potentially be employed to build more complex
nanostructures consisting of natural or unnatural
nucleotides with selective docking sites along the
single-stranded DNA.},
Doi = {10.1021/ja052491z},
Key = {05439431733}
}
@article{fds319144,
Author = {Valiaev, A and Abu-Lail, NI and Lim, DW and Chilkoti, A and Zauscher,
S},
Title = {Stimulus-responsive elastin-like polypetides as coatings for
microcantilevers: Applications for sensing and
actuation},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {230},
Pages = {U4317-U4318},
Publisher = {AMER CHEMICAL SOC},
Year = {2005},
Month = {August},
Key = {fds319144}
}
@article{fds319145,
Author = {Chow, DC and Chilkoti, A and Lee, WK and Zauscher,
S},
Title = {Rapid fabrication of DNA nanostructures by enzymatic
reactions},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {230},
Pages = {U1069-U1069},
Publisher = {AMER CHEMICAL SOC},
Year = {2005},
Month = {August},
Key = {fds319145}
}
@article{fds263364,
Author = {Valiaev, A and Dong, WL and Chilkoti, A and Schmidler, S and Zauscher,
S},
Title = {Polypeptide-solvent interactions measured by single molecule
force spectroscopy},
Journal = {Materials Research Society Symposium Proceedings},
Volume = {898},
Pages = {92-97},
Year = {2005},
Month = {January},
ISSN = {0272-9172},
url = {http://dx.doi.org/10.1557/proc-0898-l06-06-nn04-06},
Abstract = {Stimulus-responsive biomolecules have attracted a large
research interest because of their potential application in
various areas such as drug delivery, actuators and sensing
devices at the nanoscale. Using single-molecule force
spectroscopy (SMFS) we studied elastin-like polypeptides
(ELPs). These stimulus-responsive polypeptides undergo an
inverse temperature transition, accompanied by a large
conformational change, when the solvent quality is changed
by increasing the temperature or by addition of salt.
Understanding the relationship between peptide sequence and
mechanisms of force generation can provide a route to
engineer ELPs with desirable mechano-chemical properties.
Here we studied the effect of solvent quality and type of
guest residue on the mechanical properties of ELPs on the
single-molecule level. We used a novel statistical approach
to estimate polymer elasticity parameters from model fits to
the data. With this approach we were able to resolve small
changes in the Kuhn segment length distributions associated
with different molecular architectures. We then show that
these mechanical differences likely arise from differences
in the hydrophobic hydration of sidegoups, in line with
recent predictions from molecular dynamics simulations. ©
2006 Materials Research Society.},
Doi = {10.1557/proc-0898-l06-06-nn04-06},
Key = {fds263364}
}
@article{05519594637,
Author = {Chow, DC and Johannes, MS and Lee, WK and Clark, RL and Zauscher, S and Chilkoti, A},
Title = {Nanofabrication with biomolecules},
Journal = {Materials Today},
Volume = {8},
Number = {12 SUPPL. 1},
Pages = {30-39},
Publisher = {Elsevier BV},
Year = {2005},
Month = {January},
ISSN = {1369-7021},
url = {http://dx.doi.org/10.1016/S1369-7021(05)71287-6},
Keywords = {Proteins;Problem solving;},
Abstract = {The advances made in biotechnology and nanotechnology for
building complex bionanostructures on surfaces with
nanometer precision are discussed. The use of biomolecules
for nanoscale has become an effective solution for difficult
positioning problems in the fabrication of nanostructures.
To fabricate efficiently with biomolecules and make use of
their unique properties, a radical shift away from the high
energy, high vacuum processing paradigm of conventional
micro and nanofabrication is needed. An exciting
opportunities for bionanofabrication have also emerged in
the field of synthetic biology and recombinant protein
engineering.},
Doi = {10.1016/S1369-7021(05)71287-6},
Key = {05519594637}
}
@article{fds319149,
Author = {Valiaev, A and Lim, DW and Oas, T and Clark, RL and Chilkoti, A and Zauscher, S},
Title = {Force-induced proline cis-trans isomerization in
elastin-like polypeptides},
Journal = {Biophysical Journal},
Volume = {88},
Number = {1},
Pages = {168A-168A},
Publisher = {BIOPHYSICAL SOCIETY},
Year = {2005},
Month = {January},
Key = {fds319149}
}
@article{05329283237,
Author = {Kim, J and Liu, Y and Ahn, SJ and Zauscher, S and Karty, JM and Yamanaka,
Y and Craig, SL},
Title = {Self-assembly and properties of main-chain reversible
polymer brushes},
Journal = {Advanced Materials},
Volume = {17},
Number = {14},
Pages = {1749-1753},
Publisher = {WILEY},
Year = {2005},
url = {http://dx.doi.org/10.1002/adma.200401355},
Keywords = {DNA;Self assembly;Monomers;Synthesis (chemical);Electrostatics;Free
energy;Thermodynamics;Polymerization;Atomic force
microscopy;Scanning electron microscopy;Adhesives;},
Abstract = {The compressive and adhesive mechanical properties of
self-assembled polymer brushes were investigated using
DNA-based modules. The effects of surface anchor density,
association strength, and monomer flexibility on the
properties were also investigated. Reversible polymer brush
properties were examined using atomic force microscopy. It
was observed that the effective polymer brush height and
resulting adhesive interactions were strongly dependent on
surface anchor density and the thermodynamics,
concentration, and conformational flexibility of the
monomer.},
Doi = {10.1002/adma.200401355},
Key = {05329283237}
}
@article{04268228648,
Author = {Hyun, J and Lee, W-K and Nath, N and Chilkoti, A and Zauscher,
S},
Title = {Capture and release of proteins on the nanoscale by
stimuli-responsive elastin-like polypeptide
"switches".},
Journal = {Journal of the American Chemical Society},
Volume = {126},
Number = {23},
Pages = {7330-7335},
Year = {2004},
Month = {June},
ISSN = {0002-7863},
url = {http://www.ncbi.nlm.nih.gov/pubmed/15186170},
Keywords = {Polypeptides;Nanostructured materials;Nanotechnology;Lithography;Ionic
strength;Hydrophobicity;Hydrophilicity;Atomic force
microscopy;},
Abstract = {This article describes the fabrication and characterization
of stimulus-responsive elastin-like polypeptide (ELP)
nanostructures grafted onto omega-substituted thiolates that
were patterned onto gold surfaces by dip-pen nanolithography
(DPN). In response to external stimuli such as changes in
temperature or ionic strength, ELPs undergo a switchable and
reversible, hydrophilic-hydrophobic phase transition at a
lower critical solution temperature (LCST). We exploited
this phase transition behavior to reversibly immobilize a
thioredoxin-ELP (Trx-ELP) fusion protein onto the ELP
nanopattern above the LCST. Subsequent binding of an
anti-thioredoxin monoclonal antibody (anti-Trx) to the
surface-captured thioredoxin showed the presentation of the
immobilized protein in a sterically accessible orientation
in the nanoarray. We also showed that the resulting
Trx-ELP/anti-Trx complex formed above the LCST could be
reversibly dissociated below the LCST. These results
demonstrate the intriguing potential of ELP nanostructures
as generic, reversible, biomolecular switches for on-chip
capture and release of a small number (order 100-200) of
protein molecules in integrated, nanoscale bioanalytical
devices. We also investigated the molecular mechanism
underlying this switch by measuring the height changes that
accompany the binding and desorption steps and by adhesion
force spectroscopy using atomic force microscopy.},
Doi = {10.1021/ja049721e},
Key = {04268228648}
}
@article{8515974,
Author = {Kaholek, M and Lee, WK and LaMattina, B and Caster, KC and Zauscher,
S},
Title = {Fabrication of Stimulus-Responsive Nanopatterned Polymer
Brushes by Scanning-Probe Lithography},
Journal = {Nano Letters},
Volume = {4},
Number = {2},
Pages = {373-376},
Publisher = {American Chemical Society (ACS)},
Year = {2004},
Month = {February},
url = {http://dx.doi.org/10.1021/nl035054w},
Keywords = {nanolithography;nanopatterning;nanostructured
materials;polymerisation;polymers;},
Abstract = {Stimulus-responsive, surface confined poly(N-isopropylacrylamide)
(pNIPAAM) brush nanopatterns were prepared on gold-coated
silicon substrates in a "grafting-from" approach that
combines "nanoshaving", a scanning probe lithography method,
with surface-initiated polymerization using atom transfer
radical polymerization (ATRP). The reversible,
stimulus-responsive conformational height change of these
nanopatterned polymer brushes was demonstrated by inverse
transition cycling in water, and water-methanol mixtures
(1:1, v:v). Our findings are consistent with the behavior of
laterally confined and covalently attached polymer chains,
where chain mobility is restricted largely to the
out-of-plane direction. Our nanofabrication approach is
generic and can likely be extended to a wide range of vinyl
monomers.},
Doi = {10.1021/nl035054w},
Key = {8515974}
}
@article{04408386601,
Author = {Kaholek, M and Lee, W-K and Ahn, S-J and Ma, H and Caster, KC and LaMattina, B and Zauscher, S},
Title = {Stimulus-responsive poly(N-isopropylacrylamide) brushes and
nanopatterns prepared by surface-initiated
polymerization},
Journal = {Chemistry of Materials},
Volume = {16},
Number = {19},
Pages = {3688-3696},
Publisher = {American Chemical Society (ACS)},
Year = {2004},
url = {http://dx.doi.org/10.1021/cm049562y},
Keywords = {Monolayers;Lithography;Water;Nanotechnology;Actuators;},
Abstract = {In this paper we report the surface-initiated polymerization
of poly(N-isopropylacrylamide) (pNIPAAM), a
stimulus-responsive polymer, from monolayers of
ω-mercaptoundecyl bromoisobutyrate on gold-coated
surfaces. pNIPAAM was polymerized in aqueous solution at a
low methanol concentration at room temperature to maintain
the growing pNIPAAM chains in a hydrophilic and an extended
conformational state. Under these conditions thick polymer
brush layers (up to 500 nm in the swollen state) are
produced after 1 h of polymerization. We present a new and
simple strategy to fabricate stimulus-responsive,
surface-confined pNIPAAM brush nanopatterns prepared in a
"grafting- from" approach that combines "nanoshaving", a
scanning probe lithography method, with surface-initiated
polymerization. The reversible, stimulus-responsive
conformational height change of bulk and nanopatterned
polymer brushes was demonstrated by repeated cycling in
water and water/methanol mixtures (1:1, v/v). Our findings
are consistent with the behavior of laterally confined and
covalently attached polymer chains, where chain mobility is
restricted largely to the out-of-plane direction. The
present work is significant because the triggered control of
interfacial properties on the nanometer scale holds
significant promise for actuation in bio-nanotechnology
applications where polymeric actuators may manipulate the
transport, separation, and detection of biomolecules.},
Doi = {10.1021/cm049562y},
Key = {04408386601}
}
@article{05038794680,
Author = {Ahn, SJ and Kaholek, M and Lee, W-K and LaMattina, B and LaBean, TH and Zauscher, S},
Title = {Surface-initiated polymerization on nanopatterns fabricated
by electron-beam lithography},
Journal = {Advanced Materials},
Volume = {16},
Number = {23-24},
Pages = {2141-2145},
Publisher = {WILEY},
Year = {2004},
ISSN = {0935-9648},
url = {http://dx.doi.org/10.1002/adma.200401055},
Keywords = {Nanostructured materials;Gold;Methanol;Monomers;Self
assembly;Ellipsometry;Fourier transform infrared
spectroscopy;Photolithography;Electron beam
lithography;Scanning electron microscopy;},
Abstract = {A new 'top-down/bottom-up' approach for fabricating
patterned polymer-brush arrays on the micrometer and
nanometer length scales was reported. It was suggested that
patterns with well-defined feature dimensions, shapes, and
inter-feature spacings can be easily created over large
areas by lift-off electron beam lithography (EBL). The
utility of combining lift-off EBL for fabrication of Au
patterns and surface-initiated polymerization to form micro-
and nanostructures of stimulus-responsive polymer brushes on
silicon surfaces was demonstrated. The fabrication approach
was found to allow a high level of lateral control in
patterning surfaces with complex polymer-brush structures
over large surface area.},
Doi = {10.1002/adma.200401055},
Key = {05038794680}
}
@article{03487761138,
Author = {Valiaev, A and Clark, RL and Chilkoti, A and Zauscher,
S},
Title = {Conformational Mechanics of Stimulus-Responsive
Polypeptides},
Journal = {Smart Structures and Materials 2005: Active Materials:
Behavior and Mechanics},
Volume = {5053},
Pages = {31-40},
Publisher = {SPIE},
Address = {San Diego, CA, United States},
Year = {2003},
Month = {November},
url = {http://dx.doi.org/10.1117/12.484700},
Keywords = {Phase transitions;Conformations;Interfaces
(materials);Elasticity;Hydrophobicity;Molecular
structure;Molecular dynamics;Nuclear magnetic resonance
spectroscopy;Computer simulation;},
Abstract = {Stimulus-responsive polymers and polypeptides (SRPs)
experience a significant entropic response when exposed to
an environmental stimulus, such as a change in temperature.
This phase transition directly affects polymer conformation
and can potentially be harnessed for force generation in
actuation devices on nano- and micro-scales. While
interfacial applications of SRPs have been prototypically
demonstrated, a systematic investigation of the phase
transition behavior at the solid-liquid interface and on the
single-molecule level is lacking. In this paper we present
results from force-spectroscopy measurements probing the
force-extension and conformational behavior of one SRP,
elastin-like polypeptides (ELF), below and above their
transition temperature. The results indicate that there is
no significant difference in the force extension behavior at
intermediate and large extensions, but the behavior is
dramatically different at small extensions. Results also
demonstrated that above the phase transition temperature
large, unspecific adhesion forces often gave way to constant
force steps upon extension, indicating a collapsed,
potentially entangled, hydrophobic state of the ELP. The
extension behavior below the phase transition temperature,
however, closely followed that of a random polymer coil,
without any significant unspecific adhesion forces. The
excellent fit of a simple extended freely jointed chain
model to the data at intermediate and large extensions
suggests that the ELP is in a random conformational state
without significant secondary structure. Forces associated
with a phase transition therefore arise likely from entropic
conformational changes associated with a hydrophobic
collapse.},
Doi = {10.1117/12.484700},
Key = {03487761138}
}
@article{7840110,
Author = {Powers, JD and Sanders, N and Zauscher, S},
Title = {Force interactions between calcium carbonate and chemically
functionalized colloidal probes: The effect of calcium ion
and polyelectrolyte addition},
Journal = {International Paper and Coating Chemistry Symposium,
Proceedings},
Pages = {23-29},
Address = {Montreal, Que., Canada},
Year = {2003},
Month = {November},
Keywords = {adhesion;adsorption;calcium compounds;coating
techniques;fibres;monolayers;paper making;polymer
electrolytes;},
Abstract = {An understanding of fundamental interactions of micron-sized
pigments in papermaking and paper coating processes is
important in controlling the interactions between the
pigment and cellulose fibers, flocculants and binder. This
research established, for the first time, the effects of
calcium ion concentration and anionic polyelectrolyte
(sodium salt of polyacrylic acid) on interactions between a
freshly-cleaved calcite (CaCO3) surface and a
chemically-functionalized colloidal probe by direct force
measurements using an atomic force microscope. In the
absence of polyelectrolyte, adhesive interactions increased
with increasing polarity of the probe. The adhesive
interaction between calcite and a carboxylate-terminated
probe increased strongly with increasing Ca2+ ion
concentration and leveled off at about 0.1 M after most
available Ca2+ adsorption sites had been occupied. The
extent of steric interactions in the presence of
polyacrylate depended on polymer concentration and suggested
a flat polymer conformation up to monolayer coverage, and an
extended polymer conformation above full coverage.
Increasing the Ca2+ ion concentration caused a significant
compression of the polyacrylate layer, Adhesion between
CaCO3 and carboxylate-terminated probes increased with
increasing polyelectrolyte concentration. In addition, for
any given polymer concentration, adhesion increased also
with increasing Ca2+ ion concentration, suggesting a Ca2+
ion mediated polymer bridging mechanism. For a given ion
concentration, adhesion force leveled off or peaked at
approximately monolayer surface coverage of polymer. These
results will be critically discussed in context of published
data on retention of dispersed and undispersed calcium
carbonate pigments and in context of published data on the
dispersion of calcium carbonate with adsorbed
polyacrylates.},
Key = {7840110}
}
@article{03317571981,
Author = {Ahn, SJ and Lee, WK and Zauscher, S},
Title = {Fabrication of stimulus-responsive polymeric nanostructures
by proximal probes},
Journal = {Materials Research Society Symposium Proceedings},
Volume = {735},
Pages = {111-116},
Address = {Boston, MA, United States},
Year = {2003},
Month = {July},
Keywords = {Polymers;Free radical polymerization;Nanotechnology;Surfaces;Self
assembly;Gold;},
Abstract = {The triggered control of interfacial properties on the
nanometer scale holds significant promise for actuation in
bio-nanotechnology applications where polymeric actuators
may manipulate the transport, separation, and detection of
biomolecules. To fabricate patterned, stimulus-responsive
polymer brushes we have developed several methods that
combine surface initiated polymerization (SIP) with dip-pen
nanolithography (DPN). Surface-confined, stimulus-responsive
polymer brush nanopatterns were fabricated by amplification
of DPN patterned, self-assembled monolayers of
16-mercaptohexadecanoic acid on gold surfaces by SIP of
N-isopropylacrylamide (NIPAAm). While free radical
polymerization yielded only short polymer brushes (DP<50),
atom transfer free radical polymerization (ATRP) produced
thick, uniform polymer brushes. For free radical
polymerization the thickness of the polymer brush layer is a
function of the lateral feature size and the initiator
density and is maximal at pattern boundaries.},
Key = {03317571981}
}
@article{02507262693,
Author = {Garoff, N and Zauscher, S},
Title = {The influence of fatty acids and humidity on friction and
adhesion of hydrophilic polymer surfaces},
Journal = {Langmuir : the Acs Journal of Surfaces and
Colloids},
Volume = {18},
Number = {18},
Pages = {6921-6927},
Publisher = {American Chemical Society (ACS)},
Year = {2002},
Month = {September},
url = {http://dx.doi.org/10.1021/la025787g},
Keywords = {Cellulose;Friction;Adhesion;Fatty acids;Atmospheric
humidity;Hydrophilicity;Monolayers;Sorption;},
Abstract = {Monolayers of saturated fatty acids of different chain
lengths and of 9-cis-octadecenoic acid were physisorbed onto
regenerated cellulose surfaces to study their effect on
friction and adhesion. Lateral and normal force measurements
on these surfaces were carried out at different humidities
using an atomic force microscope with chemically
functionalized silicon nitride cantilevers. Friction and
adhesion of clean cellulose increased significantly with
humidity. Adhesion forces at high humidity were predicted
well by theory that accounted for the effect of the Laplace
pressure due to capillary condensation. The magnitude of
friction and adhesion and their dependence on humidity
decreased with increasing hydrophobicity of the contacting
surfaces. Friction of cellulose surfaces impregnated with
different saturated fatty acids decreased sharply from a
high level to a low level at a carbon chain length above 14
carbon atoms. Contact angle data indicated that only
saturated fatty acids with 16 carbon atoms or more in the
carbon chain formed vertically oriented monolayers on
cellulose. Our results suggest that friction of hydrophitic
polymer surfaces under ambient conditions is greatly
influenced by capillary condensation. Furthermore,
lubrication by fatty acids is achieved through the formation
of vertically oriented, hydrophobic monolayers that can
withstand the normal and shear stresses during sliding and
increase the hydrophobicity of the polymer surface, thereby
decreasing the degree of capillary condensation.},
Doi = {10.1021/la025787g},
Key = {02507262693}
}
@article{fds319161,
Author = {Zauscher, S and Garoff, N},
Title = {The influence of fatty acids and humidity on the friction of
hydrophilic polymer surfaces.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {223},
Pages = {U454-U455},
Publisher = {AMER CHEMICAL SOC},
Year = {2002},
Month = {April},
Key = {fds319161}
}
@article{7655306,
Author = {Hyun, J and Ahn, SJ and Lee, WK and Chilkoti, A and Zauscher,
S},
Title = {Molecular recognition-mediated fabrication of protein
nanostructures by dip-pen lithography},
Journal = {Nano Lett. (Usa)},
Volume = {2},
Number = {11},
Pages = {1203-1207},
Publisher = {American Chemical Society (ACS)},
Year = {2002},
url = {http://dx.doi.org/10.1021/n10257364},
Keywords = {biological techniques;monolayers;nanolithography;nanotechnology;proteins;},
Abstract = {We describe the molecular recognition-mediated, stepwise
fabrication of patterned protein nanostructures with feature
sizes on the order of 200 nm. First, a self-assembled
monolayer (SAM) of 16-mercaplohexadecanoic acid (MHA) is
patterned onto gold by dip-pen nanolithography (DPN), and
the unpatterned regions are passivated with a
protein-resistant oligoethylene glycol-terminated
alkanethiol SAM. Next, an amine-terminated biotin derivative
is covalently conjugated with the chemically activated MHA
SAM nanopattern. The surface is then incubated with
streptavidin to form streptavidin nanostructures, mediated
by molecular recognition between biotin and streptavidin.
Finally, protein nanopatterns are fabricated by molecular
recognition-mediated immobilization of biotinylated protein
from solution. Our fabrication methodology is generically
applicable because of the ubiquity of biotin-tagged
molecules},
Doi = {10.1021/n10257364},
Key = {7655306}
}
@article{fds319160,
Author = {Uner, B and Kadla, JF and Ramasubramanian, MK and Zauscher, S and Hubbe,
M and van Zanten, JH},
Title = {Determination of adhesion forces between adhesives and
metal/paper surfaces using atomic force microscopy.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {223},
Pages = {U130-U130},
Year = {2002},
Key = {fds319160}
}
@article{fds319162,
Author = {Zauscher, S},
Title = {Friction of hydrogel surfaces.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {221},
Pages = {U346-U346},
Publisher = {AMER CHEMICAL SOC},
Year = {2001},
Month = {April},
Key = {fds319162}
}
@article{01015463804,
Author = {Zauscher, S and Klingenberg, DJ},
Title = {Friction between cellulose surfaces measured with colloidal
probe microscopy},
Journal = {Colloids and Surfaces A: Physicochemical and Engineering
Aspects},
Volume = {178},
Number = {1-3},
Pages = {213-229},
Publisher = {Elsevier BV},
Year = {2001},
Month = {March},
ISSN = {0927-7757},
url = {http://dx.doi.org/10.1016/S0927-7757(00)00704-4},
Keywords = {Cellulose;Colloids;Microscopic examination;Friction;Particle
size analysis;},
Abstract = {Colloidal probe microscopy was employed to study sliding
friction between model cellulose surfaces in aqueous
solutions. Regardless of scan size, friction exhibits
irregular stick-slip behavior related to surface roughness.
At small scan sizes (∼10 nm), the coefficient of friction
decreases with increasing load. Above a critical scan size
of about 100 nm - corresponding to the average size of
asperities on one of the model surfaces - friction forces
are independent of scan size, but depend on the load.
Hydrodynamic forces contribute little to friction. Small
amounts of high molecular weight, polyelectrolytes decrease
significantly sliding friction between cellulose surfaces.
© 2001 Elsevier Science B.V.},
Doi = {10.1016/S0927-7757(00)00704-4},
Key = {01015463804}
}
@article{03457709386,
Author = {Scott, CT and Simonsen, J and Klingenberg, D and Zauscher,
S},
Title = {Pulp extrusions incorporating sludge from the pulp and paper
industry},
Journal = {Tappi Proceedings Environmental Conference and
Exhibit},
Volume = {1},
Pages = {203-211},
Address = {Denver, CO, United States},
Year = {2000},
Month = {December},
Keywords = {Pulp;Extrusion;Rheology;Drying;},
Abstract = {Pulp extrusion at ultra-high consistency (≅30% solids) has
been shown to be a viable process for converting recovered
paper, wastepaper, and papermill residues into solid sheets
and profiles. We have previously shown that extrusion of
ultra-high consistency pulps and "model" sludges requires
the addition of a water-soluble polymer (WSP) to alter the
rheological properties of the pulp such that an homogenous
"pulp paste" can be formed and extruded. This paper
discusses our attempts to evaluate the viability of
extruding a variety of papermill sludges. Several sludges
were acquired from various mills and classified by ash
content, contaminant level, and biological activity. Various
blends of sludge, newsprint (ONP), and WSP were prepared and
extruded into continuous sheets. The sheets were then cut
into strips for consolidation by press drying. These strips
were further cut into coupons for tensile testing. The
results showed that a variety of sludges could be
successfully extruded with adequate tensile strength.
However, the presence of contaminants (e.g., chips, staples,
plastics, silica) and interfering chemistries posed some
difficulties in processing these residues.},
Key = {03457709386}
}
@article{fds263349,
Author = {Zauscher, S and Klingenberg, DJ},
Title = {Normal Forces between Cellulose Surfaces Measured with
Colloidal Probe Microscopy.},
Journal = {Journal of Colloid and Interface Science},
Volume = {229},
Number = {2},
Pages = {497-510},
Year = {2000},
Month = {September},
url = {http://www.ncbi.nlm.nih.gov/pubmed/10985829},
Abstract = {Colloidal probe microscopy was employed to study
interactions between cellulose surfaces in aqueous
solutions. Hydrodynamic forces must be accounted for in data
analysis. Long-range interactions betweeen cellulose
surfaces are governed by double-layer forces and, once
surfaces contact, by osmotic repulsive forces and
viscoelasticity. Increasing the ionic strength decreases
surface potentials and increases adhesive forces.
Polyelectrolytes cause strong steric repulsion at high
surface coverage, where interactions are sensitive to probe
velocity. Polymer bridging occurs at low coverage. The
conformation of adsorbed polyelectrolytes depends on the
polymer concentration. Copyright 2000 Academic
Press.},
Doi = {10.1006/jcis.2000.7008},
Key = {fds263349}
}
@article{00075245068,
Author = {Zauscher, S and Scott, CT and Willett, JL and Klingenberg,
DJ},
Title = {Pulp extrusion for recycling wastepapers and paper mill
sludges},
Journal = {Tappi Journal},
Volume = {83},
Number = {6},
Pages = {62},
Year = {2000},
Month = {January},
Keywords = {Extrusion;Recycling;Waste paper;Sewage sludge;Paper and pulp
mills;Suspensions (fluids);Stiffness;Moisture;Composition
effects;Resins;Crosslinking;},
Abstract = {Extrusion processing offers a new method by which pulps from
recycled papers and sludges can be processed at ultra-high
consistencies to form useful products. However, the method
must surmount two problems. First, the fiber suspension must
be made to flow homogeneously to achieve good formation.
Second, processing equipment must disperse fiber flocs and
transport the highly concentrated suspension. Through the
extrusion method, mills can manufacture structural fiber
composite materials with consistent, predictable properties.
Stiffness losses caused by moisture can be controlled by the
addition of crosslinkable resins.},
Key = {00075245068}
}
@article{01226518874,
Author = {Zauscher, S and Klingenberg, DJ},
Title = {Surface and friction forces between cellulose surfaces
measured with colloidal probe microscopy},
Journal = {Nordic Pulp and Paper Research Journal},
Volume = {15},
Number = {5},
Pages = {459-468},
Publisher = {WALTER DE GRUYTER GMBH},
Address = {Stockholm},
Year = {2000},
Month = {January},
url = {http://dx.doi.org/10.3183/npprj-2000-15-05-p459-468},
Keywords = {Friction;Surfaces;Atomic force microscopy;Polyelectrolytes;Rheology;Viscoelasticity;Ionic
strength;Velocity;Surface roughness;Hydrodynamics;},
Abstract = {To better understand interactions that govern the
micro-rheological behavior of pulp fiber suspensions, we
used colloidal probe microscopy to study normal forces and
sliding friction between model cellulose surfaces in
polyelectrolyte solutions. Hydrodynamic interactions must be
accounted for in data analysis. Long-range interactions are
governed by double layer forces, and once surfaces contact,
by osmotic repulsive forces and viscoelasticity. Increasing
the ionic strength decreases surface potentials and
increases adhesive forces. Polyelectrolytes cause strong
steric repulsion at high surface coverage, where
interactions are sensitive to probe velocity. Polymer
bridging occurs at low coverage. Regardless of scan size,
friction exhibits irregular stick-slip behavior related to
surface roughness. Above a critical scan size of about 100
nm - corresponding to the average size of asperities on one
of the model surfaces - lateral forces are independent of
scan size but depend on the load. Hydrodynamic forces
contribute little to friction. Even small amounts of high
molecular weight polyelectrolytes decrease sliding friction
between cellulose surfaces significantly.},
Doi = {10.3183/npprj-2000-15-05-p459-468},
Key = {01226518874}
}
@article{fds319165,
Author = {Zauscher, S and Klingenberg, DJ},
Title = {Force imaging cellulose with colloidal probe
microscopy.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {216},
Pages = {U347-U347},
Year = {1998},
Key = {fds319165}
}
@article{98054211822,
Author = {Scott, CT and Zauscher, S},
Title = {Pulp extrusion at ultra-high consistencies},
Journal = {Tappi Proceedings Environmental Conference &Amp;
Exhibition},
Volume = {2},
Pages = {739-743},
Address = {Minneapolis, MN, USA},
Year = {1997},
Month = {December},
Keywords = {Paper and pulp mills;Natural fibers;Cellulose;Polymers;Rheometers;Waste
utilization;Viscosity of liquids;Composition effects;Tensile
strength;Elasticity;},
Abstract = {A new process for producing continuous lignocellulosic fiber
products is currently under development at the USDA Forest
Service, Forest Products Laboratory. The goal of this
exploratory research is to utilize conventional pulping
techniques to process recovered papers with high filler
contents, retain fiber integrity, and produce an engineered
extruded product. This process involves the extrusion of wet
crumb pulp (primarily derived from recovered paper) at
consistencies of 20% to 40% with small amounts of
water-soluble polymers added as hydromodifiers. The
water-soluble polymers appear to have two important
rheological functions in the extrusion process: (a) they
bind water to the fiber and (b) they add lubricity to the
pulp. A torque rheometer was used to measure the apparent
viscosity of various pulp suspensions with water-soluble
polymers. The added polymers reduce viscosity dramatically
and enhance fiber dispersion. Polymer addition levels
ranging from 1% to 3% by weight dry fiber were evaluated.
Selected pulp/polymer compositions were then processed by a
twin screw extruder. A slit die was designed to produce a
thin sheet that could be press-dried and cut into coupons
for measurement of tensile properties. Fiber orientation
appeared to be random, and tensile properties were nearly
equivalent in the flow and cross-flow directions. For most
extruded compositions, fail stress and modulus of elasticity
ranged from 10 to 20 MPa and 3 to 5 GPa, respectively. These
results indicate that pulp extrusion at ultra-high
consistencies is possible and poses a viable alternative to
the disposal of highly filled recovered papers and papermill
sludges.},
Key = {98054211822}
}
@article{fds263347,
Author = {Zauscher, S and Humphrey, PE},
Title = {Orienting lignocellulosic fibers and particles by means of a
magnetic field},
Journal = {Wood and Fiber Science},
Volume = {29},
Number = {1},
Pages = {35-46},
Year = {1997},
Month = {December},
Abstract = {Fiber and particle alignment in composite materials may be
used to tailor material and object properties to specific
performance requirements. The present research demonstrates
that alignment of ferromagnetically modified slender wood
particles in magnetic fields is feasible. Magnetic torque,
which causes rotation, increases linearly with the amount of
magnetic material on particle surfaces. Below magnetic
saturation, magnetic torque increases with increasing
strength of the applied field; closer to magnetic
saturation, torque becomes less dependent on the applied
field strength. Magnetic torque maxima occur at
field-to-particle axis angles above 45°. Polarity switches
of the applied magnetic field increase particle rotation
rates and may counter permanent magnetization, which
otherwise tends to impede full particle alignment.},
Key = {fds263347}
}
@article{fds304877,
Author = {Zauscher, S and Caulfield, DF and Nissan, AH},
Title = {Influence of water on the elastic modulus of paper part
2:Verification of predictions of the H-bond
theory},
Journal = {Tappi Journal},
Volume = {80},
Number = {1},
Pages = {214-223},
Year = {1997},
Month = {January},
Abstract = {In Part I, an extension of the theory of
hydrogen-bond-dominated solids was proposed. In Part 2, the
predictions of the extended theory are tested statistically
using recently reported measurements of elastic moduli for
24 papers over a wide range of moisture contents. Moduli
were reported both quasi-statically and ultrasonically.
Statistial analysis shows that the effect of moisture in
lowering the elastic modulus of paper is greater when the
modulus is measured quasi-statically. The rate of decrease
in the logarithm of modulus with moisture content when
measured sonically is about 75% of the rate of decrease
measured quasi-statically. The ratio of the two measured
moduli for an isotropically equivalent paper is
statistically indistinguishable from a ratio obtained from
measurements of the effectiveness of water in reducing these
elastic modull.This supports one of the new predictions of
the extended H-bond theory proposed in Part
1.},
Key = {fds304877}
}
@article{97023517057,
Author = {Zauscher, S and Caulfield, DF and Nissan, AH},
Title = {Influence of water on the elastic modulus of
paper},
Journal = {Tappi Journal},
Volume = {80},
Number = {1},
Pages = {214-223},
Year = {1997},
Keywords = {Elastic moduli;Water;Statistical methods;Moisture;Mechanical
variables measurement;Hydrogen bonds;},
Abstract = {In Part I, an extension of the theory of
hydrogen-bond-dominated solids was proposed. In Part 2, the
predictions of the extended theory are tested statistically
using recently reported measurements of elastic moduli for
24 papers over a wide range of moisture contents. Moduli
were reported both quasi-statically and ultrasonically.
Statistical analysis shows that the effect of moisture in
lowering the elastic modulus of paper is greater when the
modulus is measured quasi-statically. The rate of decrease
in the logarithm of modulus with moisture content when
measured sonically is about 75% of the rate of decrease
measured quasi-statically. The ratio of the two measured
moduli for an isotropically equivalent paper is
statistically indistinguishable from a ratio obtained from
measurements of the effectiveness of water in reducing these
elastic moduli. This supports one of the new predictions of
the extended H-bond theory proposed in Part
I.},
Key = {97023517057}
}
@article{fds304876,
Author = {Zauscher, S and Caulfield, DF and Nissan, AH},
Title = {The influence of water on the elastic modulus of paper. Part
I: Extension of the H-bond theory},
Journal = {Tappi Journal},
Volume = {79},
Number = {12},
Pages = {178-182},
Year = {1996},
Month = {December},
Abstract = {In Part I, the theory of hydrogen-bond-dominated solids is
extended to explain phenomena concerning the elastic
behavior of paper, based on the postulate that the number
dencity of effective hydrogen bonds, normalized to on
average bond stiffness, is higher for ultrasonic modulus
measurements than for quasi-static measurements. This leads
to the predictions: (I) The measured elastic modulus of a
sheet of paper will depend upon whether the modulus is
measured quasi-statically using load-elongation methods of
ultrasonically using the time of flight method, and that the
ultrasonic modulus, Es, will exceed the quasi-static
modulus, Er, (Es > Er). (2) The rate of change of modulus
with increasing moisture content, w, follows the rule: In[E]
= A - (C.I.) w, where the negative slope of the curve In[E]
vs. w is constant over a wide this of moisture contents. But
again this slope will also differ whether measured
quasi-statically or ultrasonically, with (C.I.)s > (C.I.)r.
(3) Moreover, the extended theory predicts that the ratio of
moduli at zero moisture content is related to the ratio of
slopes by the expression: {[Es]r} / [Es]}3 =[(C.I.) + I] /
[(C.I.) + I].},
Key = {fds304876}
}
@article{98124512315,
Author = {Zauscher, S and Klingenber, DJ},
Title = {Rheology and extrusion processability of pulp
suspensions},
Journal = {Proceedings of the Conference on the Use of Recycled Wood
and Paper in Building Applications},
Pages = {189},
Address = {Madison, WI, USA},
Year = {1996},
Month = {December},
Keywords = {Fibers;Rheology;Polymers;Suspensions (fluids);Strength of
materials;Composition effects;Microstructure;Flocculation;Shear
stress;},
Abstract = {The mechanism by which water-soluble polymers change
suspension rheology is examined. The effect of polymer
addition on rheology was evaluated using a torque rheometer
where large shear rates and strains prevail. The polymer
addition level for sufficient formation was found to be
higher than the equilibrium adsorption level. Linear, high
molecular-weight polymers were found to yield the largest
torque drops. Suspensions of flexible fibers were also
observed to behave as elastic solids at low shear rates.
Polymer addition has very minimal effect on network strength
at practical consistencies.},
Key = {98124512315}
}
@article{98124512289,
Author = {Zauscher, S and Scott, CT},
Title = {Pulp extrusion: A new processing method for recycling
recovered wastepaper and papermill sludge and its
application for building materials},
Journal = {Proceedings of the Conference on the Use of Recycled Wood
and Paper in Building Applications},
Pages = {68-78},
Address = {Madison, WI, USA},
Year = {1996},
Month = {December},
Keywords = {Waste utilization;Sewage sludge;Extrusion;Recycling;Building
materials;Composite materials;Strength of
materials;Stiffness;Paper and pulp mills;},
Abstract = {Fibers recovered from recycled paper products have desirable
mechanical properties and can be used for the manufacture of
composite materials. Contrary to their use in papermaking,
recycled wood pulp fibers used for composites may require
only minimal cleaning and de-inking, thus greatly reducing
manufacturing costs. In addition, waste fiber sources which
are not used presently could be exploited. In the research
presented it is shown that extrusion processing of highly
concentrated, aqueous pulp fiber suspensions offers a way to
manufacture composite materials which make use of the
inherent strength and bonding potential of wood fibers. With
this process, fiber composites with mechanical properties
comparable to those found in medium density fiberboard and
hardboard can be produced continuously. Stiffness loss due
to moisture can be controlled by addition of crosslinkable
resins, thus offering the possibility to manufacture
structural materials with consistent and predictable
properties. Tolerance of the extrusion process toward the
addition of inorganic materials make it a suitable process
for recycling contaminated fibers and papermill
sludges.},
Key = {98124512289}
}
@article{97013501034,
Author = {Zauscher, S and Caulfield, DF and Nissan, AH},
Title = {Influence of water on the elastic modulus of paper, Part
I},
Journal = {Tappi Journal},
Volume = {79},
Number = {12},
Pages = {178},
Year = {1996},
Abstract = {In Part I, the theory of hydrogen-bond-dominated solids is
extended to explain phenomena concerning the elastic
behavior of paper, based on the postulate that the number
dencity of effective hydrogen bonds, normalized to on
average bond stiffness, is higher for ultrasonic modulus
measurements than for quasi-static measurements. This leads
to the predictions: (I) The measured elastic modulus of a
sheet of paper will depend upon whether the modulus is
measured quasi-statically using load-elongation methods of
ultrasonically using the time of flight method, and that the
ultrasonic modulus, Es, will exceed the quasi-static
modulus, Er, (Es > Er). (2) The rate of change of modulus
with increasing moisture content, w, follows the rule: In[E]
= A - (C.I.) w, where the negative slope of the curve In[E]
vs. w is constant over a wide this of moisture contents. But
again this slope will also differ whether measured
quasi-statically or ultrasonically, with (C.I.)s >
(C.I.)r. (3) Moreover, the extended theory predicts that the
ratio of moduli at zero moisture content is related to the
ratio of slopes by the expression: {[Es]r} / [Es]}3 =[(C.I.)
+ I] / [(C.I.) + I].},
Key = {97013501034}
}
%% Preprints
@article{fds358988,
Author = {French, D and Navarro, L and Zauscher, S},
Title = {Bio-inspired peptide-polymer hybrid mucin analogues:
Applications in osteoarthritis and kidney stone
disease},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {257},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2019},
Month = {March},
Key = {fds358988}
}
@article{fds358989,
Author = {Navarro, L and French, D and Zauscher, S},
Title = {Synthesis of modular brush polymer-protein hybrids using
diazotransfer and copper click chemistry},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {257},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2019},
Month = {March},
Key = {fds358989}
}
@article{fds358987,
Author = {Tang, L and Deshpande, S and Yang, Y and Gu, R and Chilkoti, A and Zauscher, S},
Title = {Enzymatic synthesis of aptamer-targeted polynucleotide drugs
for cancer therapy},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {257},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2019},
Month = {March},
Key = {fds358987}
}
@article{fds358990,
Author = {Feng, Y and Huang, J and Ngaboyamahina, E and Marusak, K and Glass, J and Mikkelsen, M and Zauscher, S},
Title = {Organic ligands enhance the recombination lifetime and
photoelectrochemical performance of biosynthesized CdS
nanoparticle thin films},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {256},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2018},
Month = {August},
Key = {fds358990}
}
@article{fds358991,
Author = {Shields, W and White, J and Osta, E and Patel, J and Rajkumar, S and Zauscher, S},
Title = {Encapsulation, protection and programmed release of retinol
from silicone particles for topical applications},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {256},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2018},
Month = {August},
Key = {fds358991}
}
@article{fds358992,
Author = {Brittain, W and Rastogi, S and Zauscher, S},
Title = {The enduring utility of azobenzene as a photocontrol unit in
hybrid macromolecular systems},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {256},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2018},
Month = {August},
Key = {fds358992}
}
@article{fds358993,
Author = {Tu, Q and Lange, B and Kim, H and Yingling, Y and Blum, V and Zauscher,
S},
Title = {Subsurface structure fingerprint of 2D materials and
heterostructures by their nanomechanical
response},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {253},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2017},
Month = {April},
Key = {fds358993}
}
@article{fds358995,
Author = {Hardy, G and Shapter, J and Alam, M and Zauscher,
S},
Title = {Synthesis and characterization of supported lipid bilayer
membranes from complex lipid mixtures},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {253},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2017},
Month = {April},
Key = {fds358995}
}
@article{fds358994,
Author = {Feng, Y and Ngaboyamahina, E and Marusak, K and Glass, J and Zauscher,
S},
Title = {Hybrid (organic/inorganic) electrode design from bacterially
precipitated CdS for PEC/storage applications},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {253},
Year = {2017},
Key = {fds358994}
}
@article{fds327224,
Author = {Tkatchenko, TV and Luo, X and Tkatchenko, AV and Vaz, C and Tanavde, VM and Maurer-Stroh, S and Zauscher, S and Gonzalez, P and Young,
TL},
Title = {Large-scale microRNA expression profiling identifies retinal
miRNA-mRNA signaling pathways underlying form-deprivation
myopia in mice},
Journal = {Investigative Ophthalmology & Visual Science},
Volume = {57},
Number = {12},
Pages = {3 pages},
Publisher = {ASSOC RESEARCH VISION OPHTHALMOLOGY INC},
Year = {2016},
Month = {September},
Key = {fds327224}
}
@article{fds358996,
Author = {Rastogi, S and Gu, R and Lamas, J and Li, X and Zauscher, S and Brittain,
W},
Title = {Synthesis of photoresponsive single stranded DNA aggregates
via click chemistry},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {249},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2015},
Month = {March},
Key = {fds358996}
}
@article{fds319127,
Author = {Gu, R and Zauscher, S and Lamas, J and Brittain, W},
Title = {Synthesis of photo-responsive single-stranded DNA micelles
via copper-free click chemistry},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {248},
Pages = {2 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2014},
Month = {August},
Key = {fds319127}
}
@article{fds319128,
Author = {Hardy, G and Zauscher, S},
Title = {Hiv-1 Neutralizing Antibodies and Vaccine Antigen
Selectively Interact with Phase-Separated Model
Membranes},
Journal = {Biophysical Journal},
Volume = {106},
Number = {2},
Pages = {300a-300a},
Publisher = {Elsevier BV},
Year = {2014},
Month = {January},
url = {http://dx.doi.org/10.1016/j.bpj.2013.11.1746},
Doi = {10.1016/j.bpj.2013.11.1746},
Key = {fds319128}
}
@article{fds319129,
Author = {Tang, L and Tjong, V and Gu, R and Chilkoti, A and Zauscher,
S},
Title = {Enzyme catalyzed polymerization of DNA amphiphiles that
self-assemble into star-like micelles},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {246},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2013},
Month = {September},
Key = {fds319129}
}
@article{fds319130,
Author = {Ferris, R and Yellen, B and Zauscher, S},
Title = {Electric double layer formed by polarized ferroelectric thin
films: Implications for sensing and colloidal manipulation
in aqueous media},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {246},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2013},
Month = {September},
Key = {fds319130}
}
@article{fds319131,
Author = {Zauscher, S and Yellen, B and Ferris, R},
Title = {Programming smart macromolecular and ferroelectric surfaces
for (bio)sensing applications},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {245},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2013},
Month = {April},
Key = {fds319131}
}
@article{fds319135,
Author = {Ferris, R and Zauscher, S},
Title = {Electric field-induced nanolithography to manipulate soft
matter on surfaces},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {243},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2012},
Month = {March},
Key = {fds319135}
}
@article{fds319133,
Author = {Zauscher, S},
Title = {Molecular mechanisms of aqueous boundary lubrication by
mucinous glycoproteins},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {244},
Year = {2012},
Key = {fds319133}
}
@article{fds319134,
Author = {Ferris, R and Hucknall, A and Kwon, BS and Chilkoti, A and Zauscher,
S},
Title = {Field-induced nanolithography for the patterning of
non-fouling polymer brushes},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {243},
Year = {2012},
Key = {fds319134}
}
@article{fds319138,
Author = {Chen, T and Zhang, J and Chang, DP and Garcia, A and Zauscher,
S},
Title = {PMSE 99-Fabrication of patterned polymer brushes by in situ
crosslinking of an initiator precursor by microcontact
printing},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {236},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2008},
Month = {August},
Key = {fds319138}
}
@article{fds319143,
Author = {Abu-Lail, NI and Jay, G and Guilak, F and Zauscher,
S},
Title = {Effect of glycoproteins on friction in diarthroidal joints
and between model surfaces measured with lateral force
microscopy},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {231},
Pages = {1 pages},
Publisher = {AMER CHEMICAL SOC},
Year = {2006},
Month = {March},
Key = {fds319143}
}
@article{fds319146,
Author = {Abu-Lail, NI and Kaholek, M and Loveless, DM and Craig, SL and Zauscher,
S},
Title = {Atomic force microscopy study of reversibly crosslinked
polymer brushes},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {230},
Pages = {U4180-U4180},
Publisher = {AMER CHEMICAL SOC},
Year = {2005},
Month = {August},
Key = {fds319146}
}
@article{fds319147,
Author = {Lee, WK and Kaholek, M and Ahn, SJ and Patra, M and Linse, P and Zauscher,
S},
Title = {Progress in fabrication and characterization of
nanopatterned polymer brushes},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {230},
Pages = {U4005-U4006},
Publisher = {AMER CHEMICAL SOC},
Year = {2005},
Month = {August},
Key = {fds319147}
}
@article{fds319148,
Author = {Kaholek, M and Lee, W-K and Feng, L and LaMattina, B and Dyer, DJ and Zauscher, S},
Title = {pH, salt, and solvent sensitive polymer brush micro- and
nanopatterns fabricated by electron-beam
lithography},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {230},
Pages = {U4186-U4186},
Publisher = {AMER CHEMICAL SOC},
Year = {2005},
Month = {August},
Key = {fds319148}
}
@article{fds319150,
Author = {Abulail, NI and Ohashi, T and Clark, R and Erickson, H and Zauscher,
S},
Title = {Elasticity of fibronectin fibrils - Insights from the
relative unfolding strengths of FN-III domains and
GFP},
Journal = {Biophysical Journal},
Volume = {88},
Number = {1},
Pages = {168A-168A},
Publisher = {BIOPHYSICAL SOCIETY},
Year = {2005},
Month = {January},
Key = {fds319150}
}
@article{fds319151,
Author = {Valiaev, A and Lim, DW and Clark, R and Chilkoti, A and Zauscher,
S},
Title = {Mechanics of stimulus-responsive elastin-like polypeptides
studied by force spectroscopy.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {228},
Pages = {U485-U485},
Publisher = {AMER CHEMICAL SOC},
Year = {2004},
Month = {August},
Key = {fds319151}
}
@article{fds319152,
Author = {Abu-Lail, NI and Kaholek, M and Lam, Y and LaMattina, B and Zauscher,
S},
Title = {Micro-cantilever deflection: A tool for characterizing
polymer brush properties and biomolecular recognition
events.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {228},
Pages = {U487-U487},
Publisher = {AMER CHEMICAL SOC},
Year = {2004},
Month = {August},
Key = {fds319152}
}
@article{fds319153,
Author = {Kaholek, M and Hyun, J and Lee, WK and Chilkoti, A and Zauscher,
S},
Title = {Fabrication of "smart" biomolecular and polymeric
nanostructures using molecular recognition,
surface-initiated nanopolymerization and scanning probe
lithography.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {227},
Pages = {U861-U861},
Publisher = {AMER CHEMICAL SOC},
Year = {2004},
Month = {March},
Key = {fds319153}
}
@article{fds319154,
Author = {De Bellis and AC and Zauscher, S},
Title = {Investigation of nanoscale friction in poly(N-isopropylacrylamide)
brushes by atomic force microscopy.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {227},
Pages = {U820-U820},
Publisher = {AMER CHEMICAL SOC},
Year = {2004},
Month = {March},
Key = {fds319154}
}
@article{fds319155,
Author = {Kaholek, M and Lee, WK and LaMattina, B and Caster, K and Zauscher,
S},
Title = {Preparation and characterization of stimulus-responsive
poly(N-isopropyl-acrylamide) brushes and
nanopatterns.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {227},
Pages = {U509-U509},
Publisher = {AMER CHEMICAL SOC},
Year = {2004},
Month = {March},
Key = {fds319155}
}
@article{fds319156,
Author = {Zauscher, S and Chilkoti, A and Hyun, J and Lee, WK},
Title = {Fabrication of "smart" protein nanostructures using
molecular recognition and dip-pen nano-lithography.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {226},
Pages = {U485-U485},
Publisher = {AMER CHEMICAL SOC},
Year = {2003},
Month = {September},
Key = {fds319156}
}
@article{fds319157,
Author = {Nath, N and Chilkoti, A and Zauscher, S and Hyun, JH and Lee,
WK},
Title = {Non-covalent, environmentally modulated molecular
recognition between ELP biopolymers: A convenient route to
reversible protein arrays.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {226},
Pages = {U410-U410},
Publisher = {AMER CHEMICAL SOC},
Year = {2003},
Month = {September},
Key = {fds319157}
}
@article{fds319158,
Author = {Zauscher, S and Chilkoti, A and Ahn, SJ and Hyun, J and Lee,
WK},
Title = {Fabrication of surface confined, stimulus-responsive polymer
nanostructures using dip-pen nanolithography.},
Journal = {Abstracts of Papers of the American Chemical
Society},
Volume = {225},
Pages = {U655-U655},
Publisher = {AMER CHEMICAL SOC},
Year = {2003},
Month = {March},
Key = {fds319158}
}
@article{fds319159,
Author = {Zauscher, S and Klingenberg, DJ},
Title = {Surface forces and friction between cellulose surfaces in
aqueous media},
Journal = {Nanotribology: Critical Assessment and Research
Needs},
Pages = {411-440},
Year = {2003},
ISBN = {1-4020-7298-8},
Key = {fds319159}
}
@article{fds319163,
Author = {Zauscher, S and Scott, T and Willett, JL and Klingenberg,
DJ},
Title = {Pulp extrusion at ultra-high consistencies: a new processing
method for recycling waste papers and papermill
sludges},
Journal = {Fifth International Conference on Woodfiber Plastic
Composites},
Pages = {307-307},
Year = {1999},
Key = {fds319163}
}
@article{fds319164,
Author = {Scott, CT and Zauscher, S and Klingenberg, DJ},
Title = {Rheology and extrusion of low-grade paper and
sludge},
Journal = {Tappi International Environmental Conference, Vols 1
3},
Pages = {685-690},
Year = {1999},
ISBN = {0-89852-736-8},
Key = {fds319164}
}
%% Journal Articles
@article{fds337169,
Author = {Tang, L and Gu, R and Aritome, I},
Title = {DNA Brushes: Advances in Synthesis and Applications},
Pages = {627-654},
Publisher = {JOHN WILEY & SONS LTD},
Editor = {Azzaroni, O and Szleifer, I},
Year = {2017},
Month = {December},
ISBN = {9781119455011},
url = {http://dx.doi.org/10.1002/9781119455042.ch22},
Doi = {10.1002/9781119455042.ch22},
Key = {fds337169}
}
@article{fds327225,
Author = {Bhushan, B and Luo, D and Schricker, SR and Sigmund, W and Zauscher,
S},
Title = {Handbook of Nanomaterials Properties},
Pages = {1463 pages},
Publisher = {Springer Science & Business Media},
Year = {2014},
Month = {March},
ISBN = {3642311075},
Abstract = {This Handbook of Nanomaterials Properties will be the first
single reference work that brings together the various
properties with wide breadth and scope.},
Key = {fds327225}
}
%% Chapter in Book
@misc{fds346422,
Author = {Deshpande, S and Yang, Y and Chilkoti, A and Zauscher,
S},
Title = {Enzymatic synthesis and modification of high molecular
weight DNA using terminal deoxynucleotidyl
transferase.},
Volume = {627},
Pages = {163-188},
Booktitle = {Methods in Enzymology},
Year = {2019},
Month = {January},
url = {http://dx.doi.org/10.1016/bs.mie.2019.07.044},
Abstract = {The recognition that nucleic acids can be used as polymeric
materials led to the blossoming of the field of DNA
nanotechnology, with a broad range of applications in
biotechnology, biosensors, diagnostics, and drug delivery.
These applications require efficient methods to synthesize
and chemically modify high molecular weight DNA. Here, we
discuss terminal deoxynucleotidyl transferase
(TdT)-catalyzed enzymatic polymerization (TcEP) as an
alternative to conventional enzymatic and solid-phase DNA
synthesis. We describe biochemical requirements for TcEP and
provide step-by-step protocols to carry out TcEP in solution
and from surfaces.},
Doi = {10.1016/bs.mie.2019.07.044},
Key = {fds346422}
}
@misc{fds327151,
Author = {Zauscher, S and Parlak, Z and Tu, Q},
Title = {Polymeric and Biomolecular Nanostructures: Fabrication by
Scanning Probe Lithography},
Volume = {2},
Booktitle = {Handbook of Nanomaterials Properties},
Publisher = {Springer-Verlag, Berlin-Heidelberg},
Editor = {Bhushan, B and Luo, D and Schricker, SR and Sigmund, W and Zauscher,
S},
Year = {2014},
Key = {fds327151}
}
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