Immobilization of tyrosinase in poly(ethyleneoxide) electrodes and determination of phenolics in red wines

Polyphenol oxidase was immobilized in thiophene capped poly(ethyleneoxide)/polypyrrole (PEO/PPy) and 3-methylthienyl methacrylate-co-p-vinyl benzyloxy poly(ethyleneoxide)/polypyrrole (CP/PPy) matrices. Immobilization of the enzyme was performed via entrapment in conducting copolymers during electrochemical polymerization of pyrrole through the thiophene moiety 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 red wines of Turkey was analyzed using these electrodes.