An amperometric enzyme electrode for glucose using immobilized glucose oxidase in a ferrocene attached poly(4-vinylpyridine) multilayer film

An amperometric enzyme electrode for glucose has been prepared by immobilized glucose oxidase (GOD) in a multilayer film based on a thiol self-assembled monolayer at a gold electrode. The multilayer film of GOD and ferrocene attached poly(4-vinylpyridine) (Fc-PVP) complex is formed by electrostatic force. Fc-PVP as a polyelectrolyte in which ferrocene is as a mediator, acts with GOD to form a complex. The linear range of the enzyme electrode is extended up to 10mmol/L of glucose due to the addition of 5 GOD layers. The enzyme electrode is sensitive to glucose, 0.10 mmol/L glucose leads to a response current of 22nA and the detection limit is down to 0.01 mmol/L. Ascorbic acid and uric acid have no interference for the determination of glucose. The enzyme electrode is stable over 3 weeks.