Complexes of glutathione with heavy metal ions as a new biochemical marker of aquatic environment pollution.
Reduced glutathione (GSH) plays a number of key roles in many biochemical pathways. This peptide is highly reactive and forms conjugates with other molecules via its sulfhydryl moiety. The interactions of the common heavy metal pollutant Cd(II) with GSH were determined by using the Brdicka reaction to evaluate whether this technique would be suitable as a biomarker. After GSH interaction with Cd(II) ions, two characteristic changes in the measured voltammogram were observed: Cat2 signal height decreased, and a new signal called P1 was found. The observed signal probably relates to the formation of a GSH-heavy metal ion complex adsorbed on the surface of the working electrode. When the interaction of GSH with cisplatin was studied, the same characteristic changes in the voltammogram were observed, which confirmed our hypothesis. Moreover, changes in the height of P1 and Cat2 signals with increasing time of GSH interaction with Cd(II) ions and/or cisplatin were also investigated. Cat2 peak height decreased proportionally with increasing time of interaction. This decrease can be explained by shielding of free sulfhydryl moiety by heavy metal ions, so it cannot catalyze the evolution of hydrogen from the supporting electrolyte. In addition, we found that, with increasing time of the interaction, the P1 signal was enhanced and shifted to more positive potentials for both Cd(II) ions and cisplatin.
Baloun
Jiri
J
Department of Chemistry and Biochemistry, Mendel University of Agriculture and Forestry, Zemedelska 1, Brno, Czech Republic.
Adam
Vojtech
V
Trnkova
Libuse
L
Beklova
Miroslava
M
Svobodova
Zdenka
Z
Zeman
Ladislav
L
Kizek
Rene
R
D015415:Biomarkers; D002945:Cisplatin / Q000737:chemistry; D004563:Electrochemistry; D004784:Environmental Monitoring / Q000379:methods*; D005978:Glutathione / Q000737:chemistry*; D019216:Metals, Heavy / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D015415:Biomarkers; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D005978:Glutathione; D002945:Cisplatin