Collect. Czech. Chem. Commun. 1989, 54, 2105-2119

The polarographic and voltammetric determination of 5-(3-phenoxysulphenylazo)-6-hydroxy-3-cyano-1,4-dimethyl-2-pyridone

Jiří Barek, Ivana Švagrová-Hauserová and Jiří Zima

Department of Analytical Chemistry, Charles University, 128 40 Prague 2


The polarographic reduction of the title azodye has been studied, a mechanism was proposed and optimal conditions were found for the determination of this substance by TAST polarography in the range 5.10-5-2.10-6 mol l-1 and differential pulse polarography at a dropping mercury electrode in the range 5.10-5-2.10-8 mol l-1. The sensitivity was further increased by adsorptive accumulation of the determined substance on the surface of a hanging mercury drop electrode with linear scan voltammetry (determination limit 5.10-10 mol l-1). The selectivity was increased by prior separation of the determined azodye using thin layer chromatography and by transferring the substance adsorbed on the surface of the hanging mercury drop to a new base electrolyte solution.