Enzymatically prepared poly(hydroquinone) as a mediator for amperometric glucose sensors

Poly(hydroquinone) (PHQ), synthesized from glucose-β-D-hydroquinone by peroxidase-catalyzed polymerization in aqueous solution and placed on glassy carbon electrodes, behaves as a redox mediator for glucose sensing. The highly selective nature of enzymatic catalysis leads to PHQ with a unique structure which is more soluble in organic solvents and more electrochemically active, as compared to that prepared via electrochemical methods. A glucose sensor is constructed in a pellet form with PHQ, glucose oxidase (GOD) and graphite powder. PHQ retains its redox activity and reversibility in the solid state and effectively mediates the electron transfer between the electrode and GOD. Resulting glucose biosensors possess sub-minute response times over a dynamic range from 1 to 30 mM. The PHQ mediator permits sensor operation at 100 mV (versus SCE), thereby reducing susceptibility toward common endogenous, easily oxidizable interferences.