Chemical reactions of As complexation by glutathione: an XAFS study

16th International Conference on X-ray Absorption Fine Structure

Franco, M.W.^1 ; Vasconcelos, I.F.^2 ; Modolo, L.V.^3 ; Barbosa, F.A.R.^1

Laboratory of Limnology, Ecotoxicology and Aquatic Ecology-LIMNEA, Universidade Federal de Minas Gerais, Belo Horizonte, MG

31.270-901, Brazil^1

Department of Metallurgical and Materials Engineering, Universidade Federal Do Ceará, Campus do Pici Bloco 714, Fortaleza, CE

60455-760, Brazil^2

Department of Botany, Universidade Federal de Minas Gerais, Belo Horizonte, MG

31.270-901, Brazil^3

关键词: Complex formations;    Glutathiones;    Intracellular reduction;    Molar ratio;    Target compound;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012088/pdf
DOI  :  10.1088/1742-6596/712/1/012088

来源: IOP

【 摘 要 】

In this study, the chemical reactions between As(III) and As(V) with glutathione, which is a target compound in As biochemistry due to its primordial role in As immobilization and intracellular reduction, in various molar ratios were investigated using As K-edge XAFS spectroscopy. Results showed a gradual substitution of As-O bonds in the coordination of aqueous As(III) and As(V) for three As-S bonds in the As+GSH complex. Moreover, the data showed reduction of As(V) to As(III) prior or concomitant to the As+GSH complex formation.