| Molecular imprinting is a polymer synthesis technique which has a predetermined recognition ability for target molecule. The stability of physical and chemical property, ease of 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.In this study a phenylurea herbicides-selective molecularly imprinted polymer (MIP) was prepared using N-(4-isopropylphenyl)- N′-butyleneurea as a dummy template and toluene as a porogen. The experimental results showed that the optimum molar ratio of template, functional monomer (MAA) and cross-linker (EDMA) is 1:8:20. The prepared MIP showed an obvious class-selectivity for phenylurea herbicides in the mobile phase of weak polarity. The experimental and calculated results also indicated that the recognition site is mainly located at the N′position of phenylurea herbicides. The Molecular imprinting solid phase extraction (MISPE) was developed for phenylurea herbicides in tap water using MIP prepared as separation materials and the recoveries of monuron, isoproturon, fenuron, chlortoluron, difenoxuron and metoxuron were more than 60%.In addition, in this study a molecularly imprinted polymer for genistein was prepared by using genistein as a template, 4-VP as a monomer and EDMA as a cross-linker in THF. The prepared MIP showed a high affinity and selectivity for genistein and daidzein in acetonitrile containing less then 5% water as the mobile phase. The experiments indicate that the imprinted sites of genistein-MIPrecognize genistein by the hydrogen binding interaction with hydroxyl groups of 5, 7, 4′position of genistein molecule. The MISPE of genistein from crude extract of kudzu root was developed and the results indicated that the recoveries of genistein in crude extract of kudzu root and ethyl acetate extract of kudzu root after MISPE were 70% and 50% respectively.
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