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Updated: Jun 28, 2026

A Study of the Complexation of Mercury(II) with Dicysteinyl Tetrapeptides by Electrospray Ionization Mass Spectrometry
Published on: January 8, 2016
Formation constants of some mercury(II) complexes determined from their anodic polarographic signals
M Esteban1, E Casassas, L Fernandez
1Departament de Química Analítica, Facultat de Química, Universitat de Barcelona, Av. Diagonal 647, 08028 Barcelona, Spain.
Abstract:
The formation constants of some Hg(II) complexes have been determined from the anodic polarographic signals for the oxidation of mercury in the presence of the following ligands: thiourea and its phenyl- and diphenyl-derivatives, thiocyanate, ethylenediamine, EDTA, methylthioacetic acid, 2,2'-thiobisacetic acid, 3,3'-thiobispropanoic acid, 2,2'-[1,1-methandiylbis(thio)]bisacetic acid and 2,2'-[1,2-ethandiylbis(thio)]bisacetic acid. The use of differential pulse polarography and a.c. polarography instead of d.c. polarography increases the accuracy and precision of the potential measurements and, as a consequence, of the stability constants determined. The results obtained by the different methods are compared.
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