SOL-GEL-DERIVED NANOCRYSTALLINE GOLD-SILICATE COMPOSITE BIOSENSOR

A new class of sol-gel-derived electrochemical biosensors is introduct ed and demonstrated for glucose sensing. The electrode material compri ses an interconnected dispersion of gold nanocrystals imbedded in a po rous methyl silicate matrix. The gold nanoparticles provide electrocat alysis and electric conductivity; the methyl groups endow hydrophobici ty and limit the active area of the exposed gold, thus decreasing the background current; the silicate provides a transparent and porous bac kbone; and the encapsulated glucose oxidase provides biocatalysis.