AMPEROMETRIC GLUCOSE BIOSENSOR BASED ON SOL-GEL ORGANIC-INORGANIC HYBRID MATERIAL

A new type of sol-gel organic-inorganic hybrid material was developed and used for the production of biosensors. This material is composed o f silica sol and a grafting copolymer of poly(vinyl alcohol) with 4-vi nylpyridine. It prevents the cracking of conventional sol-gel-derived glasses and eliminates the swelling of the hydrogel. The optimum compo sition of the hybrid material was first examined, and then glucose oxi dase was immobilized in this matrix to demonstrate its application. Th e characteristics of the biosensor were studied by cyclic voltammetry and chronoamperometry. The biosensor exhibited a series of good proper ties: high sensitivity (600 nA mmol(-1)L(-1)), short response time (11 s) and remarkable long-term stability in storage (at least 5 months). In addition, the characteristics of the second-generation biosensor w ith the use of tetrathiafulvalene as a mediator mere discussed.