Immobilization of polyphenol oxidase in conducting graft copolymers and determination of phenolic amount in red wines with enzyme electrodes

Abstract

Polyphenol oxidase was immobilized in several conducting copolymer matrices. Three different types of poly(methyl methacrylate-co-methyl thienyl methacrylate) matrices were used to obtain copolymers. Immobilization of enzyme was carried out by the entrapment of the enzyme in conducting copolymer matrices during electrochemical polymerization of pyrrole through thiophene moieties of the polymers. Maximum reaction rates, Michaelis–Menten constants, optimum temperature and pH values and operational stabilities of the enzyme electrodes were investigated. Total amount of phenolic compounds in some Turkish red wines was analyzed using these electrodes.