Sol-gel-derived nanocrystalline gold-silicate composite biosensor

A new class of sol-gel-derived electrochemical biosensors is introduced and demonstrated for glucose sensing. The electrode material comprises an interconnected dispersion of gold nanocrystals imbedded in a porous methyl silicate matrix. The gold nanoparticles provide electrocatalysis and electric conductivity; the methyl groups endow hydrophobicity and limit the active area of the exposed gold, thus decreasing the background current; the silicate provides a transparent and porous backbone; and the encapsulated glucose oxidase provides biocatalysis.