Immobilization of antibodies on ultraflat polystyrene surfaces

Background: Functional antibody surfaces were prepared on ultraflat polysty rene surfaces by physical adsorption, and the uniform distribution of monoc lonal antibodies against hepatitis B surface antigen (anti-HBs) on such sur faces and the presence of dense hepatitis B surface antigen (HBsAg) particl es captured by immobilized antibodies were identified. Methods: A model polystyrene film was spin-coated directly onto a silicon w afer surface. Atomic force microscopy was used to directly monitor the immo bilization of anti-HBs antibodies and their specific molecular interaction with HBsAg. Enzyme immunoassay was also used to characterize functional ant ibody surfaces. Results: A mean roughness of 2 Angstrom for areas of 25 mu m(2) was produce d. We found a uniform distribution of anti-HBs antibodies on ultraflat poly styrene surfaces and the presence of dense HBsAg particles bound to such an ti-HBs surfaces after incubation with HBsAg. Conclusions: This study confirmed the potential of preparing dense, homogen eous, highly specific, and highly stable antibody surfaces by immobilizing antibodies on polystyrene surfaces with controlled roughness. It is expecte d that such biofunctional surfaces could be of interest for the development of new solid-phase immunoassay techniques and biosensor techniques. (C) 20 00 American Association for Clinical Chemistry.