Modification of the surface of integrated optical wave-guide sensors for immunosensor applications

Methods have been developed which enable attachment amino and epoxy groups to the surface of integrated optical wave-guide sensors for immunosensor applications. The SiO2-TiO2 surfaces were modified by use of the trifunctional silane reagents gamma-aminopropyltriethoxysilane (APTS) and gamma-glycidoxypropyltrimethoxysilane (GOPS) in organic and/or in inorganic phases. Silanization methods were optimized taking into consideration the concentration of silane reagent used and the temperature and time of reaction. To evaluate the layers formed, immobilization experiments were undertaken on the modified surfaces using the bovine serum albumin (BSA)-anti-BSA IgG antibody model molecule pair. The regenerability of the sensitized surfaces was also studied.