Effects of Tin Oxide Sputtered on a Carbon Electrode for Fabricating Glucose Biosensor

Abstract

Tin oxide thin films are sputtered onto a commercial carbon electrode to develop a electrode. A mediator (ferrocene carboxylic acid) and an enzyme (glucose oxidase) are coimmobilized by polyvinylalcohol bearing styrylpyridinium groups on the surface of the carbon and electrodes, to fabricate carbon and amperometric glucose biosensors. Following electrode modification, the applied potential is reduced from and the current response increases from as the carbon and amperometric glucose biosensors are immersed in glucose solution. The detection limit of the carbon amperometric glucose biosensor is under an applied potential of . Furthermore, when the applied potential is set to , the detection limit of the amperometric glucose biosensor reaches . No significant interference is observed when the applied potential is set at . Furthermore, the glucose concentration determined by the glucose presence in the serum sample agrees closely with that in the buffer solution. The merits of reducing the applied potential and increasing current response enable a highly accurate amperometric glucose biosensor based on a low-cost substrate to be developed in this study.