Functionalized biopolymers as soluble macromolecular chelating agents

Two different conjugates of bovine serum albumin (BSA) with lysine and deri vative of imidazole have been synthesized to obtain watersoluble macromolec ules with binding properties against bivalent transition metal ions. Synthe ses have been carried out using the 60 aminogroups or the 99 carboxylic gro ups on BSA for the coupling reactions, with such molar ratios able to produ ce highly substituted BSA. The skill of each conjugate to bind metal ions in aqueous medium was studie d through the use of titration curves with some metal ions, characterized b y a good affinity for the free ligand. Both the conjugates allow us to reco ver a high number of metal ions per protein molecule, close to the number o f ligand molecules on the BSA surface in the case of the lysine conjugate, whereas in the case of the imidazole conjugate M3L complexes are performed.