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 modify a carbon paste electrode. The modified electrode was characterized by cyclic 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 nitroimidazole and nitrofurane compounds. However, this effect was not observed on the reduction of nitrobenzene derivatives such as nitrobenzene substituted 1,4-dihydropyridines. Conditions such as pH and percentage of DMF have been optimized for the determination of these nitro-compounds. The best electrocatalytic reactions were obtained at pH 8.5, coincident with the optimal activity of the enzyme.