Modified platinum wire glucose oxidase amperometric electrode

Abstract

A flow injection system incorporating a modified platinum wire amperometric enzyme electrode is described. Glucose oxidase was covalently attached to an activated platinum surface to form an enzyme electrode, which was then incorporated in a laboratory-built three-electrode flow-through cell. The system exhibited good linearity (for glucose concentrations of 0.1–20 mM), where log (current/A)= 0.992 log ([glucose]/M)–3.94, with a correlation coefficient of 0.999. Response times (<25 s) and wash times (<30 s) were short, and a lifetime of 9 h was obtained for continuous exposure to 2.5 and 10 mM glucose. Normal use during the flow injection analysis of glucose gave lifetimes of 10 d.