Glucose Sensor Based on Nickelocene Blended Carbon Paste Electrode

Suppression of Enzyme Leaking from Electrode Surface

Abstract

An amperometric glucose sensor based on carbon paste electrode containing glucose oxidase, nickelocene, and platinum particles was fabricated and characterized. The sensor was functional at a less extreme potential (-200 mV vs. Ag/AgCl) than those of amperometric mediator free sensors. The sensor worked not only in buffer solution but in serum. The output current was unaffected by ascorbate, whose concentration was about two orders of magnitude above the standard ascorbate concentration in human blood. Although the sensor response decreased gradually when native-enzyme was coblended, the sensor in which the enzyme was modified with methoxy-polyethylene-glycol-epoxy was much stabler due to the suppression of enzyme leakage than that with native-enzyme coblended.