分子烙印聚合物对神经性毒剂降解产物固相吸附行为研究

Solid phase extraction behavior of molecularly imprinted polymers for nerve agent degradation products

目的:本研究以神经性毒剂降解产物为模板分子,在不同反应条件下合成了系列分子烙印聚合物 (MIP)作为固相萃取(SPE)填料,以评价和研制一种神经性毒剂降解产物的选择性吸附剂,并研究其吸附机制和影响因素。方法:分别以VX的水解产物甲基膦酸乙酯(EMPA)、俄罗斯VX的水解产物甲基膦酸异丁酯 (i BuMPA)和梭曼的水解产物甲基膦酸片呐酯(PMPA)为模板分子合成MIP,并填充自制MIP SPE小柱,气相色谱检测,考察功能单体、交联剂、溶剂、温度及MIP粒子的大小等因素对MIP吸附性能的影响。结果:实验表明功能单体和交联剂的种类和用量及模板分子的结构是影响MIP吸附性能的重要因素。以丙烯酰胺为功能单体、乙二醇二甲基丙烯酸酯为交联剂合成的MIP适用于对神经性毒剂降解产物吸附行为的考察。以神经性毒剂降解产物为模板分子合成的MIP对各降解产物均呈现较强的吸附,其吸附率与降解产物的结构呈一定相关性。结论:合成的系列MIP可作为通用的神经性毒剂降解产物的选择性吸附剂,用于对样品中神经性毒剂降解产物的萃取。

Objective: To evaluate and screen out a new selective solid phase sorbent for nerve agent degradation products and study the influencing factors and mechanism of molecularly imprinted polymers(MIPs).Methods:A series of MIPs were synthesized with nerve agent degradation products(such as EMPA, i-BuMPA and PMPA, they are the degradation of VX, RVX and GD respectively) as template with different functional monomers, crosslinker and solvent and were used as solid phase extraction(SPE) sorbents. The adsorption ratio of MIPs to the nerve agent degradation products in acetonitrile solution was determined by derivative GC. Influences of functional monomers, crosslinker, progenic solvent, temperature and the granularity of MIP etc. on the recognition behavior were investigated. Results: The recognition ability of the MIPs were strongly influenced by the type and amount of monomer and crosslinker. The experiment indicated that MIP prepared using acrylamide as monomer and ethylene-glycol dimethacrylate as crosslinker was most suitable MIP for corresponding templates. On the other hand, the structure of template was another important factor influencing MIP′s binding behavior. MIPs synthesized could strongly adsorb the six nerve agent degradation products. The ratio of adsorption of MIPs was relevant to the structure of the degradation products. Conclusion: MIPs synthesized could be used as common sorbents for extraction, separation and enrichment of nerve agent degradation products in practical samples.