Oxidation of NO mediated by water-soluble iron porphyrin

An anodic voltammetric wave of NO catalyzed by meso-tetra(N-methyl-4-pyridy l) iron(III) pentachloride ([Fe-III(TMPyP)](5+)) was found in a phosphate b uffer solution (pH 7.4). The current was 10 times larger than the diffusion -controlled current of NO without the iron porphyrin. The current can be us ed to detect NO in aerobic physiological environments. Spectroelectrochemic al measurements suggested the formation of iron-nitrosyl complex, which is responsible for the catalytic oxidation of NO. The intermediate of the cata lytic oxidation was detected by spectroelectrochemistry. (C) 1999 Elsevier Science S.A. All rights reserved.