Fabrication of glucose oxidase/polypyrrole biosensor by galvanostatic method in various pH aqueous solutions

摘要

The pH effect of pyrrole electropolymerization in the presence of glucose oxidase (GOD(x)) on the performance and characteristic of galvanostatically fabricated glucose oxidase/polypyrrole (Ppy) biosensor is reported. Preparing the GOD(x)/Ppy biosensors in 0.1 M KCl saline solution with various pH containing 0.05 M pyrrole monomer and 0.5 mg/ml GOD(x) at 382 muA/cm(2) current density for 100 mC/cm(2) film thickness, both the galvanostatic responses and characteristics of these resulted biosensors were obtained. The results revealed that the galvanostatic glucose biosensor fabricated at neutral pH condition exhibited much higher sensitivity than those fabricated at lower or higher pH conditions, and had a good linearity form zero to 10 mM glucose with the sensitivity of 7 nA/ mM. Finally, the long-term stability and the kinetic parameters, Michaelis constant and maximum current, of this biosensor were also reported. (C) 2003 Elsevier B.V. All rights reserved. [References: 18]