Hydrogen Peroxide Biosensor Based on the Direct Electrochemistry of Myoglobin Immobilized in Poly-3-Hydroxybutyrate Film

Abstract

Direct electrochemistry of myoglobin (Mb) was observed in a stable film composed of a natural lipid polymer (poly-3-hydroxybutyrate) and Mb, the film of which was modified on a pyrolytic graphite electrode. The apparent formal potential of Mb was at about -260 mV in an acetate buffer solution with pH 5.0. Moreover, Mb in the polymer film exhibited catalytic activity towards the reduction of hydrogen peroxide (H2O2). Consequently, an unmediated biosensor for H2O2 was prepared with a linear range from 1.0×10-7 to 4.0×10-4 M.