Biologically relevant silver-glutathione complexes. A XAS study to establish key structures responsible for toxicity and detoxication

A comprehensive Ag K-edge XAS study of oligomeric and polymeric complexes formed by glutathione (GSH) and silver ions is proposed, to complement and provide structural edge to spectroscopic and spectrometric characterization of these complexes. The main issues to be solved are the mode of coordination of Ag (S only vs. S+O), the coordination number (2 vs. 2/3) and the formation of ring oligomers vs. infinite chain polymers. All three issues are fundamental to the understanding of formation of Ag/GSH complexes in cells upon the dissolution of toxic silver nanoparticles and their role in detoxication vs. toxicity of silver.