An amperometric biosensor for uric acid determination prepared from uricase immobilized in polyaniline-polypyrrole film

Abstract

A new amperometric uric acid biosensor was developed by immobilizing uricase by a glutaraldehyde crosslinking procedure on polyaniline-polypyrrole (pani-ppy) composite film on the surface of a platinum electrode. Determination of uric acid was performed by the oxidation of enzymatically generated H 2O2 at 0.4 V vs. Ag/AgCl. The linear working range of the biosensor was 2.5×10-6 - 8.5×10-5 M and the response time was about 70 s. The effects of pH, temperature were investigated and optimum parameters were found to be 9.0, 55 °C, respectively. The stability and reproducibility of the enzyme electrode have been also studied.