对羟基苯甲酸乙酯印迹聚合物固相微萃取制备及条件优化

采用分子印迹技术,以对羟基苯甲酸乙酯(模板分子):α-甲基丙烯酸(功能单体):乙二醇二甲基丙烯酸酯(交联剂)摩尔比为1∶4∶20,反应温度为80℃,反应时间为15h,本体聚合的方法合成印迹聚合物。利用微量进样器和玻璃毛细管自制分子印迹固相微萃取装置。将自制固相微萃取与气相色谱联用,并对萃取头的萃取条件如萃取温度、萃取时间、解析时间、溶液离子强度等进行优化。通过选择性吸附实验测得,分子印迹固相微萃取对对羟基苯甲酸甲酯、对羟基苯甲酸乙酯和对羟基苯甲酸丙酯的萃取量分别为103.54、134.26和114.68μg,均大于非分子印迹固相微萃取的萃取量47.88、49.24和41.41μg,印迹萃取头表现出了良好的吸附性和选择性。

Synthesis and Evaluation of Ethylparaben Molecularly Imprinted Polymer-coated Solid Phase Microextraction Fiber

A novel molecular imprinted polymer(MIP) was applied to a solid phase microextraction(SPME) device,which was coupled directly to a gas chromatograph(GC).The MIP-coated solid phase microextraction(MI-SPME) fibers were prepared by using ethylparaben(EtP) as the template.They were prepared under optimum polymerization conditions: the ratio of template,functional monomer and cross-linking agent was 1∶4∶20,the initiator was 2,2-azoisobutyronitrile(AIBN,2% in 10mL acetonitrile),the reaction temperature and time were 80℃ and 15 h.In order to obtain higher extraction efficiency,the extraction temperature,time,ion strength and desorption time were optimized,and then the extraction yield of EtP of the MI-SPME fibers was higher than that of the non-imprinted polymer(NIP)-coated SPME(NI-SPME) fibers.The MI-SPME fibers also exhibited higher selectivity to other parabens with structures smilar to EtP.