Wiring of glucose oxidase to carbon matrices via sol-gel derived redox modified silicate

A new type of porous, composite material is synthesized and used for direct wiring of active enzymes. The material is comprised of a dispersion of graphite powder and redox enzymes incorporated in hybrid, pendant ferrocenyl-, alkylamine- and methyl- modified silicate backbone. Each species in this integrated construction accomplishes a specialized task; the percolating graphite powder provides conductivity, the silicate provides highly crosslinked, rigid backbone, which is used to cage the redox enzymes; ferrocene functional groups are responsible for the signal transduction from the active center of the enzyme to the percolating graphite; amine groups were incorporated for their high affinity to excess negative charges on the surface of glucose oxidase; and finally, the combination of methyl- and amine- groups is advantageous to maintain a control over the thickness of the wetted electroactive section of the electrode. Amperometric sensing of glucose demonstrates the application of this new material.