Collect. Czech. Chem. Commun. 1993, 58, 295-309

The Polarographic and Voltammetric Determination of N,N-Dimethyl-4-amino-3'-nitroazobenzene

Jiří Bareka, Dana Dřevínkováa, Viktor Mejstříkb and Jiří Zimaa

a UNESCO Laboratory of the Environmental Electrochemistry, Department of Analytical Chemistry, Charles University, 128 40 Prague 2, Czech Republic
b Toxicological Department, Research Institute of Organic Synthesis, 532 18 Pardubice-Rybitví, Czech Republic


The polarographic reduction of N,N-dimethyl-4-amino-3'-nitroazobenzene was studied by tast polarography and differential pulse polarography, constant potential coulometry and cyclic voltammetry and mechanism was proposed for the reduction. Optimal conditions were found for the determination of the test substance using tast polarography in concentration range 1 . 10-4 - 2 . 10-6 mol l-1, differential pulse polarography at classical dropping mercury electrode and fast scan differential pulse voltammetry at a hanging mercury drop electrode in range 1 . 10-4 - 2 . 10-7 mol l-1 and linear scan voltammetry at a hanging mercury drop electrode in range 1 . 10-5 - 2 . 10-8 mol l-1. A further increase in the sensitivity was achieved through adsorptive accumulation of the test substance on the surface of the working electrode, permitting the determination to be carried out in the concentration range 1 . 10-7 - 2 . 10-9 mol l-1.