Study on Electrosynthesis of Nonconducting Polyaniline Used as a Permselective Membrane in Glucose Oxidase Electrode*

Abstract

Nonconducting polyaniline (PANI) is electrosynthesized at the Au electrode in 0.05 mol/l aniline solution (pH 7.0) by the potential-scan methods of 0.0–0.9 V (vs. SCE) and ν = 0.14 V/s. This polyaniline membrane has permselectivity to H₂O₂ and can prevent uric and ascorbic acids from diffusing to electrode surface. The glucose oxidase (GOD) electrode is prepared with the nonconducting polyaniline as an exclusive membrane. The response time, linear response range, and sensitivity of the PANI–GOD electrode are 30–35 s, 0.02–22.0 mmol/l, and 2.5 nA/mmol/l, respectively. Responses for glucose at GOD and PANI–GOD electrodes are similar. But oxidation currents of uric and ascorbic acids at PANI–GOD are smaller. The response currents of these two interferences will be restrained if the PANI–GOD electrode is used to detect the glucose in human blood.