Abstract: A molecularly imprinted polymer (MIP) with specific molecule identification properties for L-carnitine was synthesized on the surface of modified silica, using L-carnitine as template molecule, ethyleneglycol dimethacrylant (EGDMA) as the cross-linker, methacrylic acid (MAA) as functional monomer and 2,2'-azobisisobutyronitrile (AIBN) as the initiator respectively. The binding effect of the complex formed between the template and the functional monomer were obtained by UV spectrophotometry. The MIP was characterized by IR spectroscopy and SEM, and the results demonstrated the formation of a grafted polymer layer on the modified silica gel surface.The absorption kinetics experiments indicated that compared with non-imprinted polymer, MIP showed better recognition ability and absorptivity. Moreover, the polymer was investigated in static adsorption equilibrium experiments and the Scatchard analysis to evaluate the adsorption characteristics. The results showed that the homogeneous binding sites were formed in the MIP, and the dissociation constants (Kd) and the apparent maximum number (Qmax) of binding sites were estimated to be 2.76 x 10-4 mol/L and 71.00 μmol/g, respectively.The selective binding experiment for substrates shows that the affinity and selectivity of the MIP for L-carnitine are higher than those for D-carnitine and two other different substrates. MIP also showed good selectivity for L-carnitine through the resolution experiments.
Template and target information: L-carnitine
Author keywords: Surface-molecular imprinting, L-carnitine, methacrylic acid, chiral recognition, Specific adsorption