Fabrication of Repeatedly Usable Pt-Electrode Chip Coated With Solidified Glucose Oxidase and Ascorbate Oxidase for the Quantification of Glucose in Urine

A repeated usable electrode sensor for the measurement of glucose in urine has been developed. For improvement of the selectivity in measuring glucose in urine, we fabricated the Pt electrode coated with multilayered composite of glucose oxidase (GOX) and ascorbate oxidase (AOX). This simple layer structure could deliver more electrons from glucose oxidation without interference from ascorbic acids by first oxidizing the ascorbic acids present in urine. Results showed that our newly developed Pt electrode is capable of quantifying the concentrations of glucose in urine in the range between 0 and 1000 mg/dL, as well as maintaining its detection stability during 200 times of repeated measurements. This repeatable use of the sensor is attributable to the solidified structure of AOX and GOX layer.