Papers Published

  1. Yang, Z.P. and Chilkoti, A., Light-activated affinity micropatterning of proteins, Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings, vol. 2 (1999), pp. 738 - [IEMBS.1999.803893] .
    (last updated on 2007/04/12)

    Protein micropatterning has attracted considerable interest because of its prospective application in the fabrication of biosensors and tissue engineering substrates. Motivated by these potential applications, we have developed a method to micropattern proteins onto self-assembled monolayers (SAMs) on gold, which we term light-activated affinity micropatterning of proteins (LAMP). LAMP is a multi-step patterning process: first, a gold substrate is modified with a mixture of 11-mercapto-undecanol and 16-mercaptohexadecanoic acid to provide a non-fouling, reactive SAM template on gold. Next, the carboxylic acid terminal groups in the binary SAM are coupled to methylnitropiperonyloxy-carbonyl biotin, (`caged' biotin) through a diamine linker, resulting in a mixed MeNPOC-biotinyl/OH-terminated monolayer. Activation of the caged biotin by spatially-defined UV illumination at 350-360 nm reconstitutes biotin in the illuminated region, allowing streptavidin or anti-biotin antibody to be localized in the illuminated regions. We have investigated each fabrication step in LAMP by a variety of surface analytical techniques, including contact angle goniometry, ellipsometry, surface plasmon resonance, and X-ray photoelectron spectroscopy to optimize ligand density and pattern contrast. LAMP can be further extended to spatially-resolved micropatterning of multiple biomolecules by repeated cycles of spatially-defined activation, streptavidin incubation, followed by binding of the biotinylated moiety of interest.

    Proteins;Gold;Photolithography;Carboxylic acids;Ultraviolet radiation;Antibodies;Goniometers;Ellipsometry;X ray photoelectron spectroscopy;