J. Phys. IV France 04 (1994) C9-299-C9-302
Pharmaceutical silver doped clays : an EXAFS study from silver to silicon K-edges absorptionF. Keller-Besrest1, S. Benazeth2, 3 and Ch. Souleau2
1 Laboratoire de Biomathématiques et Physique, UFR de Pharmacie, Université Paris V, René Descartes, 4 Avenue de l'Observatoire, 75270 Paris, France
2 Laboratoire de Chimie-Physique Minérale et Bioinorganique, Faculté de Pharmacie, Université Paris XI, 92296 Châtenay Malabry, France
3 LURE, Bât. 209D, Centre Universitaire d'Orsay, 91405 Orsay, France
The remarkable adsorption properties of the montmorillonite clay are used to elaborate a silver doped clay, intented to a therapeutical application to burns. The unstable properties of the material obtained lead us to examine the localization of the added silver in the clay matrix by EXAFS spectroscopy performed at the Ag and Si K-edge. The results show that Ag atoms formed in triangular clusters are coordinated to the triangular designs of oxygen atoms on the border plane of the layers of the clay. The local negative charge in the border plane explains the reduction of Ag+ ions, at the origin of the unstability observed for this material.
© EDP Sciences 1994