Modified electrodes with synthetic biocatalytic membranes.

A biocatalytic membrane based on an immobilized enzyme molecule has been prepared. Oxidative electropolymerization of 8-hydroxyquinaldine (8-OHQ) monomers in 0.2 M, pH 7 phosphate buffer containing glucose oxidase (GOx) has been carried out to modify the surfaces of GC, Au, and Pt rotating disk electrodes. The biocatalytic properties of the synthesized membrane were characterized by studying the catalytic activities of the immobilized GOx. Signals obtained from modified GC electrodes with this biomembrane were mainly attributed to the immobilized GOx. Signals obtained from modified Pt or Au electrodes were due to the combined contribution of the enzyme and the native electrode's material. The potential analytical applications of these modified electrodes as bioelectrochemical sensors were also investigated.