Electrochemical behavior and voltammetric determination of some nitro-substituted benzamide compounds

Voltammetric behaviors of six nitro-substituted benzamides, which are potential prodrug candidates for nitroreductase-based cancer therapy, were investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The electrochemical behavior of aromatic nitro (ArNO2) compounds by CV indicates that compounds involve various reduction/oxidation steps including the formation of aromatic nitro radical, nitroso, hydroxylamine, and amine groups. Applicability of the voltammetric determination of these prodrug candidates was studied by recording their DPVs, carried out in mixed media (Britton Robinson buffer solution + DMF) at various pH values on a pencil graphite electrode (PGE). Results show that the PGE can offer a disposable, low-cost, and sensitive electrochemical determination method for identifying nitro benzamide compounds. Under the experimental conditions, the PGE had a linear response range from 0.5 to 100 mu M 4-nitro- N-(2-nitrophenyl)benzamide (compound 2). This voltammetric procedure indicates that nitro-substituted benzamide drugs can be successfully determined in pharmaceutical samples.