Microsensors with Detection Range of Glucose to Higher Concentrations by Regulating Oxygen Concentration with the Electrolysis of Water

Abstract

We describe an improvement of the detectable range of glucose oxidase (GOx)-based microsensors to higher concentrations. Oxygen consumed by the enzyme reaction of GOx was detected cathodically by the microelectrode modified with poly(dimethylsiloxane) (PDMS) and GOx layers. PDMS was used to prevent the permeation of hydrogen peroxide that was produced by the enzyme reaction. The prepared microsensors were positioned above microband electrodes which were used to produce oxygen by the electrolysis of water, allowing a high oxygen concentration (0.8 mM) to be maintained around the microsensors. By applying this system, the detectable concentration range for glucose was extended up to 20 mM.