Voltage-controlled enzyme-catalyzed glucose-gluconolactone conversion using a field-effect enzymatic detector

The field-effect enzymatic detection (FEED) technique was used to control the kinetics of the enzymatic conversion of glucose to gluconolactone. The glucose-gluconolactone conversion occurring at an enzyme-immobilized electrode, a well-studied process, was confirmed using mass spectrometry. Electrochemical studies showed that the glucose oxidation current depends on the gating voltage V and the ion concentration of the sample solution. Additionally, the depletion of glucose in the sample also showed a dependence on V . FEED was used to detect HO on the zepto-molar level in order to show the ultrasensitive detection capability of the technique. These results, while providing evidence for the proposed mechanism of FEED, indicate that V controls the conversion process. The effect of V on the glucose-gluconolactone conversion was demonstrated by the observed V-dependent kinetic parameters of the conversion process. © 2013 the Owner Societies.