Voltammetric determination of benzidine and its derivatives, at a glassy-carbon electrode

Conditions have been found for the determination of benzidine, o-tolidine, o-dianisidine, 3,3'-diaminobenzidine and 3,3'-dichlorobenzidine by classical and differential pulse voltammetry at a glassy-carbon stationary or rotating electrode, in the concentration range 10(-5)-10(-3)M. The mechanism of the oxidation is discussed and applications are presented for the determination of these chemical carcinogens and their mixtures either directly, or after preliminary separation by extraction or thin-layer chromatography.