Papers by Author: Zhen Xing Wang

Abstract: Polymers imprinted with (S)-(-)-1,1’-bi (2-naphthol) and (R)-(+)-1,1’-bi (2-naphthol) have been prepared by non-covalent imprinting. A combinational procedure was used to optimize the functional monomer and crosslinker. A copolymer of 2-vinylpyridine and divinylbenzene resulted in the best chiral recognition. The ratio of template to functional monomer and solvent in the pre-polymerization mixture were also optimized. The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). The molecularly imprinted polymers (MIPs) were more selective when prepared using a less polar solvent. Effective separations of the enantiomers of racemic (±)-1, 1’-Bi (2-naphthol) were achieved by use of acetonitrile as mobile phase; no cross-selectivity was observed. Interactions between functional monomers and template were investigated by 1H NMR spectroscopy. The results suggest that hydrogen-bonding between the functional monomer and the template and π-π stacking interaction between the cross-linker and the template may contribute to chiral recognition.

Abstract: Silica gel was modified with polymerizable double bonds on the surface. Then the molecular imprinting polymer imprinted with D-Phenylalanin was grafted on the surface of modified silica gel. The molecularly imprinted polymer (MIP) based on the surface of silica gel was characterized by IR and scanning electron microscopy (SEM). The adsorption property of D-Phenylalanin by MIP was mearsured. The MIP with the combined functional monomers exhibited better adsorption properties and selectivity compared with the corresponding non-imprinted polymers or MIP with the single functional monomer. The material could be used in separation research field, such as packing material of high performance liquid chromatography, solid-phase extraction and so on.