L-薄荷酮分子印迹体系的计算模拟及聚合物的制备

Molecular Simulation and Preparation of Molecularly Imprinted Polymers with L-Menthone as Template

以L-薄荷酮为模板分子,通过Hyperchem8.0计算模拟,从4种单体:对乙烯基苯甲酸(VBA)、甲基丙烯酸(MAA)、丙烯酰胺(AM)、丙烯酸(AA)中优化出功能单体,制备出L-薄荷酮分子印迹聚合物。通过红外光谱分析、场发射扫描电镜、静态吸附实验、Scatchard分析及等温吸附模型分析对聚合物的外貌形态、吸附性能及印记效果进行了表征。结果表明,L-薄荷酮与甲基丙烯酸所形成复合物的作用力最强,由红外光谱研究发现,L-薄荷酮与甲基丙烯酸之间存在氢键,与分子模拟的结果一致。与非印迹聚合物相比,印迹聚合物对模板分子有较强的吸附作用,最大表观吸附量是47.84μmol/g,且在研究浓度范围内印迹聚合物对印迹分子只存在一种结合位点,符合Langmuir等温吸附模型。

A molecular simulation method was presented for molecularly imprinted polymerization system using L-Menthone as template and 4-Vinylbenzoic acid （VBA）, methacrylic acid （MAA）, acrylamide （AM）, and acrylic acid （AA） as functional monomers. The optimal geometry configuration, energy, reaction ratio and binding energy of the pre-polymerization systems were simulated by a semi-empirical method （PM3） and Amber MM methods with Hyperchem 8.0 sotlware. The monomer which provided the largest binding energy was then chosen for the synthesis of molecularly imprinted polymers （MIPs）. The results showed that MAA gave stronger bonding interaction with L-Menthone than other monomer molecules. The resultant MIPs were characterized by field emission scanning electron microscope （FESEM）, FT-IR analysis, static adsorption test, Scatchard analysis and adsorption model evaluation. FT-IR analysis demonstrated that the hydrogen bonding interaction was the main force between L-Menthone and MAA, which was conformed to the simulation results. The static adsorptive experiment indicated that the adsorption amount of MIPs to L-Menthone was stronger than non-molecularly imprinted polymers （NMIPs）. Scatchard analysis and adsorption isotherms model evaluation indicated that there was only one kind of recognition site in L-Menthone-MIPs with the max adsorption capacity （Qmax） of 47.84 μmol/g, and adsorption process of MIPs was in accord with Langrnuir adsorption model.