This Small Business Innovation Research Phase II project is designed to develop a versatile, facile, and cost effective coating of plastic materials used in microchip and biosensor systems. Passivation of the surface with a biomolecule-compatible stablizing agent, patterned imobilization of biomolecules, and other critical obstacles to the commercial development of bisensor technology will be resolved with a photoreative "universal binding" thin film surface. Covalent phototechnical bonding of the passivating agent and of the high affinity general ligand (biotin) derivative, will be done quickly under mild reaction conditions by patterned and uniform illumination, respectively. This passivated, hydrophobic "virtual well" array surface will then be useful for essentially any nucleic acid probe or specifc analyte binding protein (e.g., antibody) assay by printing with the desired ligands for the chosen analytes (e.g., oligonucleotides for nematode genes). Specific aims include the demonstration of a plastic microscope slide array with 16 sites/mm2 of X-avidin, stable to ambient storage for at least 3 months and providing a specific binding signal at least twenty times that of its noise signal in a probe hybridization assay. This program is expected to generate custom plastic microchips with up to 16,000 analyte sites per microscope slide, hydrophobic passivated slides with general binding ligands for customer printing of analyte arrays, and photoreative "virtual well" arrays on plastic slides and plates. These products comprise a major part of a rapidly growing market of $1 billion in the near term.
