Preparation, Characterization and Catalytic Activities of Immobilized Enzyme Mimics

In order to find highly active and selective oxygen-transfer catalysts with appreciable durability, Cu(II)–histidine complexes were covalently grafted onto a chlorinated polystyrene resin as copper-containing enzyme mimics. The Cu(II)-histidine complexes and the mobile polymer were to resemble the active center and the proteomic skeleton of the enzymes, respectively. The resulting heterogenized complexes were expected to be nearly so active and more durable catalysts that are easier to recycle than their homogeneous counterparts. The substances were tested in a superoxide radical anion dismutation reaction. Control for the syntheses was exerted by protecting either the N-terminal or the C-terminal of the covalently grafted l-histidine molecules. During the preparative work generally applied methods of synthetic organic chemistry (alkylation or esterification) were used. Various anchored complexes were prepared and characterized by classical analytical methods, different forms of spectroscopy as well as molecular modeling. The covalently grafted complexes having the protected amino acids as ligands displayed remarkably high activities in the superoxide dismutase (SOD) test reaction.