Interactions Silice Métallique-Soluté: Possibilité d'Applications en Préconcentration et en Chromatographie d'Echange de Ligands (LEC)

Abstract

The interactions between three different types of chelating silica loaded with transition metals and various organic solutes have been investigated. For this purpose a microcolumn containing 40 to 50 mg of stationary phase was used. The solutes, diversely charged at pH 7, contain heteroatoms and thus can bind to transition metals. The mechanisms that govern the retention of organic compounds in ligand exchange chromatography (LEC) and in selective preconcentration on metalated silicas are described. The potential applications of metal-loaded silica in LEC or in preconcentration depend on the type of the complex formed. Whereas the formation of an inner-sphere complex is favorable for preconcentration purposes an outer-sphere complex will be preferred in LEC techniques.