EFFECT OF QUATERNIZATION OF THE GLUCOSE-OXIDASE WIRING REDOX POLYMER ON THE MAXIMUM CURRENT DENSITIES OF GLUCOSE ELECTRODES

Redox polymers based on the poly(vinylpyridine) complex of [Os(bpy)(2) Cl](+/2+) were quaternized with methyl iodide, and the quaternized pol ymers were used to ''wire'' glucose oxidase. Quaternization enhanced b oth the rate of electron transport in cross-linked redox hydrogels con taining glucose oxidase and the strength of the electrostatic complex formed between the polycationic redox polymer and the polyanionic gluc ose oxidase. Quaternization with methyl groups also decreased the numb er of pyridine rings available for cross-linking by the water soluble cross-linker poly(ethylene glycol) diglycidyl ether. The current densi ties of glucose electrooxidation increased with the degree of quaterni zation of the ''wires'' until one-third of the pyridine rings were qua ternized, and the activation energies decreased until one-half of the rings were quaternized.