title: High-density immobilization of antibodies onto nanobead-coated cyclic olefin copolymer plastic surfaces for application as a sensitive immunoassay chip.
abstract: Our research efforts have been devoted to development of nanobead multilayer-based sensitive immunoassays on cyclic olefin copolymer (COC) plastic surfaces. To facilitate nanobead attachment and impart antibiofouling properties to a COC substrate, we used an amphiphilic copolymer comprising benzyl, polyethylene glycol, and reactive ester moieties to coat the hydrophobic COC surface in an aqueous environment. Subsequently, NH2-modified polystyrene nanobeads were reacted with the polymer-coated COC surface and further assembled into multilayers that increased the overall surface area available for attaching capture antibodies. After treatment of the nanobead multilayers with an amine-reactive homobifunctional crosslinker, a model capture antibody (anti-rabbit IgG) was covalently immobilized onto the activated surface of nanobeads. Finally, a sandwich immunoassay was carried out using rabbit IgG as a target analyte and rhodamine-labeled anti-rabbit IgG as a probe. Compared with a nanobead-free, polymer-coated COC surface, the nanobead multilayer-based immunoassay exhibited ~4-fold higher fluorescence intensity. In addition, our nanobead-based assay system exhibited a wide dynamic range of detection (0.1 to 1,000 ng/mL) and high specificity for rabbit IgG. Furthermore, much better detection sensitivity for rabbit IgG was attained in the nanobead multilayer-based immunoassay than with a conventional ELISA system (0.1 ng/mL versus 10 ng/mL), indicating the potential value of the proposed immunoassay system in plastic-based portable biochip applications.
authors.affiliation: Department of Medical System Engineering, Institute of Medical System Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 500-712, Republic of Korea.
authors.forename: Daekyung
authors.initials: D
authors.lastname: Sung
authors.affiliation: Department of Medical System Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 500-712, Republic of Korea.|Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Buk-gu, Gwangju, 500-712, Republic of Korea.|School of Mechatronics, Gwangju Institute of Science and Technology (GIST), 123 Cheomdan-gwagiro, Gwangju, 500-712, Republic of Korea.
authors.forename: Sung
authors.initials: S
authors.lastname: Yang
authors.affiliation: BioHealth IT Convergence Research Department, IT Convergence Technology Research Laboratory, Electronics and Telecommunications Research Institute (ETRI), 218 Gajeong-ro, Yuseong-gu, Daejeon, 305-700, Republic of Korea.
authors.forename: Jeong Won
authors.initials: JW
authors.lastname: Park
authors.affiliation: KAIST Institute for the Biocentury, Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon, 305-701, Republic of Korea. syjon@kaist.ac.kr.|Graduate School of Nanoscience and Technology (WCU), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon, 305-701, Republic of Korea. syjon@kaist.ac.kr.
authors.forename: Sangyong
authors.initials: S
authors.lastname: Jon
mesh_terms: D000818:Animals; D055910:Antibodies, Immobilized / Q000737:chemistry* / Q000276:immunology; D057219:Biofouling / Q000517:prevention & control; D003516:Cycloparaffins / Q000737:chemistry*; D007118:Immunoassay / Q000295:instrumentation*; D008863:Microspheres; D036103:Nanotechnology / Q000295:instrumentation*; D010969:Plastics / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D055910:Antibodies, Immobilized; D003516:Cycloparaffins; D010969:Plastics