Synthesis of Photoreactive Poly(ethylene oxide)s for Surface Modification.

Photoreactive polymers that generate active species upon irradiation with light are very useful for modifying the surfaces of substrates. However, water solubility decreases as the number of photoreactive functional groups on the polymer increases because most photoreactive functional groups are hydrophobic. In order to improve the hydrophilicity of the photoreactive polymer, we synthesized polyethylene glycol-based photoreactive polymers bearing hydrophobic azidophenyl groups on their side chains. Because of the hydrophilicity of the ethylene glycol main chain, polymers with large numbers of azidophenyl groups were solubilized in protic solvents compared to hydrophobic alkylene chain-based polymers prepared by radical polymerization of methacrylate monomers. Polymers were immobilized on various substrates by irradiation with ultraviolet light and were shown to suppress nonspecific interactions between proteins and cells on the substrate. We conclude that such polymers are useful, highly water soluble antifouling agents.

Novel microarrays for simultaneous serodiagnosis of multiple antiviral antibodies.

We developed an automated diagnostic system for the detection of virus-specific immunoglobulin Gs (IgGs) that was based on a microarray platform. We compared efficacies of our automated system with conventional enzyme immunoassays (EIAs). Viruses were immobilized to microarrays using a radical cross-linking reaction that was induced by photo-irradiation. A new photoreactive polymer containing perfluorophenyl azide (PFPA) and poly(ethylene glycol) methacrylate was prepared and coated on plates. Inactivated measles, rubella, mumps, Varicella-Zoster and recombinant Epstein-Barr viruse antigen were added to coated plates, and irradiated with ultraviolet light to facilitate immobilization. Virus-specific IgGs in healthy human sera were assayed using these prepared microarrays and the results obtained compared with those from conventional EIAs. We observed high correlation (0.79-0.96) in the results between the automated microarray technique and EIAs. The microarray-based assay was more rapid, involved less reagents and sample, and was easier to conduct compared with conventional EIA techniques. The automated microarray system was further improved by introducing reagent storage reservoirs inside the chamber, thereby conserving the use of expensive reagents and antibodies. We considered the microarray format to be suitable for rapid and multiple serological diagnoses of viral diseases that could be developed further for clinical applications.