Molecularly Imprinted Polymers with Mandelic Acid as Template

In this report, molecularly imprinted polymers (MIPs) with racemic and L-mandelic acid as the templates were synthesized. Several structural analogues were chosen to study the selectivity of the MIPs prepared using 4-vinylpyridine (4-VP) as the monomer (MIP4-VP). At the same time, the chromatographic behaviors of the MIP using acrylamide (AA) as the monomer (MIPAA) in two different mobile phases, acetonitrile and hexane/ethyl acetate (1:1, v/v), were investigated and the separation of the enantiomers was tried. The results indicated that MIP4-VP had great retention with a template comparable to other analogues. However, no difference in the k' values of the enantiomers was observed, as the interaction between the polymer and the enantiomers was mainly dependent on the acidity, which showed no difference. The MIPAA showed a more obvious imprinting effect for the template in hexane/ethyl acetate (1:1, v/v) than in acetonitrile. But the separation of the enantiomers was not achieved even in the less polar solvent, though there was an obvious difference between the retention time of L-MA and D-MA on the L-MA imprinted polymer.