(596a) Preparation Of Copper-Imprinted Silica Gels Functionalized With Glycine Oligomers And Their Adsorption Properties

In this presentation, we report a new procedure of modifying the surface of silica gels with glycine, diglycine and triglycine in the presence of copper ions to create a new type of copper-imprinted sorbent, which exhibits high adsorption capacity and selectivity for copper ions. The high adsorption capacity observed for the copper-imprinted silica gel is attributed to the stable copper complexes formed with two adjacent glycine, diglycine or triglycine molecules with proper intermolecular distances obtained from the ion-imprinting procedure. Another possible reason is that the ion-imprinting procedure prevents the surface from over-crowding; therefore, copper ions can form very stable 1:1 complexes with immobilized diglycine or triglycine. Interestingly, the imprinting effect is even more pronounced when the adsorption experiments are conducted in the presence of competing metal ions such as magnesium and calcium.