Study on the mechanism of binding specificity of metoclopramide-imprinted polymers.

A series of metoclopramide (MCP)-imprinted polymers utilizing methacrylic acid or 2-vinylprindine (2-VP) as functional monomer and chloroform, acetonitrile or methanol as porogen were prepared. The affinity and specificity of these polymers were evaluated by equilibrium binding experiments. Proton NMR model studies on interactions between the template and functional monomer analogues, acetic acid and d5-pyridine, were performed in the same solvents that were used as porogens for the molecularly imprinted polymers (MIPs). A correlation was found to exist between the binding strength and specificity of a particular polymer and the extent of monomer-template interactions shown by the corresponding NMR spectrum. So, a useful means is provided to predict the performance of a MIP in this paper. Based on the results of NMR experiments and selectivity experiments, the role of functional groups of the template in the formation of complementary interacting sites in the polymer in different porogens was discussed, and the mechanism of molecular recognition of the MIPs was proposed.