ELECTRON-TRANSFER AND ELECTROCHEMICAL CATALYSIS USING COBALT-RECONSTITUTED MYOGLOBIN IN A SURFACTANT FILM

Reductions of the protein myoglobin reconstituted with cobalt(III) hem e [MbCo(III)] were accomplished in liquid crystal films of didodecyldi methylammonium bromide (DDAB) on pyrolytic graphite (PG) electrodes in pH 7 buffer. Slow electron transfer to MbCo(III) was detected by squa re wave voltammetry, and a well-defined, reversible cyclic voltammogra m was observed for the MbCo(II)/MbCo(I) redox couple with a formal pot ential of - 0.85 V versus SCE and 25 mV peak potential separation at 1 00 mV s(-1). The MbCo(III)/MbCo(II) couple mediated the reduction of o xygen, while the MbCo(II)/MbCo(I) couple mediated the reduction of eth ylene dibromide. (C) 1998 Elsevier Science S.A. All rights reserved.