A sensor for investigating the interaction between biologically important heavy metals and glutathione

Abstract

Glutathione (GSH) is a water-soluble tripeptide playing a crucial role in the number of cellular reactions including detoxification of heavy metals. Glutathione can be found both in an oxidized (GSSG) and reduced (GSH) state. The aim of this paper was to use electrochemical methods to determine glutathiones and to investigate interactions of GSH and cadmium, zinc, copper and nickel ions or feed additive for animal nutrition. It clearly follows from the results that GSH and GSSG can be distinguished by cyclic voltammetry whereas the level of their current response is proportional to their concentration. Moreover, we studied these interactions by cyclic voltammetry. Marked changes in the GSH signal were observed and discussed. The highest decrease in a GSH reductive signal is caused by cadmium ions followed by zinc, nickel and copper ones. We also observed that the reductive GSH signal gradually decreased (about 9%) with the increasing concentration of feed additive used in our experiments. In conclusion, cyclic voltammetry offers a tool for studying interactions of thiols with different substances such as heavy metals and/or feed additives.