| Molecular Imprinting Technique is a new technique, which have the predetermined selectivity and recognition ability for the target molecules. Molecular imprinted polymers (MIPs) have cavity structure which is highly complementary to target molecule, as a result, the specificity recognition capability is very surprising.In addition, the stability of physical and chemical property, simple preparation, and low cost of molecularly imprinted polymers have led to their applications in many fields such as chromatographic separation, sensors, mimic enzyme catalysis, membrane separation and solid phase extraction. The molecularly imprinted monolithic columns (MIMC) prepared by in situ polymerization of monomers have not only the high stereo selectivity of MIPs, but also some advantages of simple preparation procedures, good reproducibility, low backpressure of column and low-consumption of template molecules. MIPs prepared by bulk polymerization have not only high selectivity and good recognition ability, but also some advantages of simple preparation device, easily controlled condition, conveniently popularization. In this paper, several MIPs based on the above-mentioned methods have been developed, and successfully applied to selectivity and recognition ability of environmental pesticide residue, some drugs, phytohormone. However, for some biological samples whose biological recognition mainly occurs in aqueous solution and the application of MIPs were limited to some extent. So it is extremely important to prepare MIPs that are able to go on biological recognition in aqueous solutions. These results extended the applications of MIPs in analytical chemistry. The foucus of this paper has been listed as follow:(1) Monolithic columns(MTC) were synthesized using 2,4-dichlorophenoxyacetic acid(2,4-D) as template molecules by in situ thermal-initiated polymerization method, which was used to be the stationary phase of the high performance liquid chromatography. The polymers were characterized with infrared spectrum, morphology was also analyzed with scanning electron microscopy and surface area analysis. The trends of retention factors of imprinted and blank MTC synthesized under different conditions were investigated. Furthermore, effects of methanol content, pH and flow rate on the separation performance of MIMC were discussed. Result show: The stationary phase of MIMC synthesized under optimization of preparation conditions could entirely separate 2,4-D and its analogues phenoxyacetic acid. The separation of 2,4-D from the distill liquid of orange on MIMC were tested with good result.(2) Monolithic columns were synthesized using naringenin as template molecules by in situ thermal-initiated polymerization method, which was used to be the stationary phase of the high performance liquid chromatography, selectivity and recognition ability of MIPs were studied. The trends of retention factors of imprinted and blank MTC synthesized under different conditions were investigated.Furthermore, effects of methanol content, pH on the separation performance of MIMC were discussed. The polymers morphology were characterized with scanning electron microscopy and surface area analysis. The MIPs has been successfully applied to the determination of naringenin in the Chinese traditional medicine with good results.(3) Molecular imprinted polymers were prepared using 4-chlorophenoxyacetic acid(4-CPA) as template molecules by thermal-initiated bulk polymerization method. In order to investigate the binding performance of the MIPs and blank polymers, their binding isotherm was determined. The polymer show much higher binding capacity for 4-CPA than the non-imprinted polymer with the same chemical composition. Scatchard analysis showed only one class of binding sites was formed in the imprinted polymer under the studied concentration. The experiment which MIPs was studied the selective recognition to 4-CPA and analogs, revealed that MIPs showed higher and better selective recognition abilities to 4-CPA.
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