Reduction of different nitro-compounds on electroenzymatic system: Cytochrome c reductase-NAD(P)H modified carbon paste electrode

A flavoenzyme cytochrome c reductase NAD(P)H mixture has been used to modif y a carbon paste electrode. The modified electrode was characterized by cyc lic voltammetry varying the scan rate and temperature. Cathodic and anodic peaks were observed at -0.45 and -0.39 V, respectively, for a scan rate of 100 mV/s. The enzyme-electrode is found to reduce electrocatalytically nitr oimidazole and nitrofurane compounds. However, this effect was not observed on the reduction of nitrobenzene derivatives such as nitrobenzene substitu ted 1,4-dihydropyridines. Conditions such as pH and percentage of DMF have been optimized for the determination of these nitro-compounds. The best ele ctrocatalytic reactions were obtained at pH 8.5, coincident with the optima l activity of the enzyme.