Immobilization of invertase and glucose oxidase in conducting H-type polysiloxane/polypyrrole block copolymers

Abstract

Abstract In this study, immobilizations of enzymes, invertase and glucose oxidase, were achieved in conducting copolymers of N-pyrrolyl terminated polydimethylsiloxane/polypyrrole (PDMS/PPy) matrices via electrochemical polymerization. The kinetic parameters, vmax (maximum reaction rate) and Km (substrate affinity), of both free and immobilized enzymes were determined. The effect of supporting electrolytes, p-toluene sulfonic acid and sodium dodecyl sulfate, on enzyme activity and film morphologies was examined. The optimum temperatures and operational stabilities of immobilized enzymes were determined. PDMS/PPy copolymer matrix was found to exhibit significantly enhanced properties compare to pristine polypyrrole in terms of relative enzyme activities, kinetic parameters and operational stabilities.