AbstractThe electrochemical study of the peptidic fragment Lys‐Cys‐Thr‐Cys‐Cys‐Ala 56–61 MT I (FT) alone and in the presence of cadmium was performed, by cyclic voltammetry using a hanging mercury drop electrode, in order to enable comparisons between the behavior of Cd, Zn metallothioneins and that of this less complex molecule, intrinsic to the metallothionein structure. The influence of the equilibration time, of the scan rate, and of the solution pH was investigated. The influence of the addition of cadmium with different Cd–FT ratios was also studied. Samples containing both Cd and FT give complex voltammograms showing different peaks. Several electrochemical systems were distinguished: the mercury electrode itself is involved in the charge transfer step in the presence of thiol groups coming from the FT structure; another system can be attributed to the oxido‐reduction of cadmium either as free ion or complexed by the peptide. The adsorption phenomena play an important role in the electrochemical process. Both dissolved and adsorbed species ar
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