Binding study on 5,5-diphenylhydantoin imprinted polymer constructed by utilizing an amide functional group Original Research Article

The molecular imprinting technique was applied for the preparation of a polymer selective for an acidic drug, 5,5-diphenylhydantoin in a polar solvent using acrylamide as the hydrogen-bonding functional monomer. The binding characteristics of the imprinted polymer were evaluated by batch methods. Scatchard analysis showed that two classes of binding sites were formed in the imprinted polymer. Their dissociation constants were estimated to be 9.05 μmol/l and 1.87 mmol/l, respectively, by utilizing the model of multiple independent classes of binding sites. These results were more reasonable than those obtained by the Scatchard equation. Factors that influenced rebinding of the imprinted polymer including pH, template/monomer ratio and functional monomers were explored. By contrast, when methacrylic acid was used as functional monomer, the molecular imprinted polymers made in tetrahydrofuran exhibited only very weak binding capacity for the template molecule. Finally, the substrate selectivity of imprinted polymer was investigated.