一种基于分子印迹技术的新型固相萃取填料

【作者】 罗鹏；

【导师】 徐伟箭；

【作者基本信息】 湖南大学 ， 应用化学， 2002， 硕士

【摘要】 分子印迹技术是一种制备具有特定选择性和亲合能力的分子识别材料的新兴技术：在模板分子存在的情况下，功能单体与交联剂共聚制得高交联的聚合物网络，移去模板分子后就得到了对其具有特定“记忆”效应的印迹聚合物。分子印迹技术近年来获得蓬勃发展，已被应用于分离材料、人工抗体、模拟酶催化、仿生传感器等领域。本论文利用分子印迹技术，以α-甲基丙烯酸为功能单体，二甲基丙烯酸乙二醇酯为交联剂，偶氮二异丁腈为引发剂在紫外光引发条件下合成了分别以茶碱和咖啡因为模板分子的印迹聚合物，并对聚合反应条件进行了讨论。采用紫外分光光度法对印迹聚合物的吸附性能和选择性识别能力进行了研究，用茶碱印迹聚合物为固相萃取填料，考察了它对茶碱的固相萃取，并讨论了影响其萃取性能的因素。最后从茶叶水样中进行茶碱的固相萃取，并进行了反复实验以考察它的可重复性。实验结果表明：聚合条件的不同对印迹聚合物的吸附和识别性能有相当大的影响，同样条件下以茶碱为模板的印迹聚合物其性能要优于以咖啡因为模板的印迹聚合物：单体-模板摩尔比例为4：1的印迹聚合物性能要优于摩尔比例为2：1和6：1的印迹聚合物；另外使用氯仿为反应溶剂其效果要好于乙腈。用茶碱印迹聚合物作为固相萃取填料，发现清洗溶剂、洗脱溶剂的选择和流速对萃取效果有很大影响，用其来进行茶叶水样中的茶碱固相萃取，结果通过HPLC分析表明：茶碱能够有效的被选择性富集而洗脱下来，回收率达到84． 3％，重复使用十次后回收率仍有79． 8％，证明了其良好的稳定性。更多还原

【Abstract】 MoIecula-r imprinting technology is a kind of new-emerging polymerizingtechnology which produces molecule recognition materials with high selectivity andaffinity Polymerization is occurred between functional monomers and crosslinkeraround template molecules. After extTaction of the template molecules, molecularimprinted polymers (MIPs) with specifically memory to the temp1ate molecules areobtained. Molecular imprinting technology has become more and more popular inrecent years. MIPs have been aPplied in the field of separation materials, artificialantibodies, enZyIne mimic catalyst, mimic biosensors etc.In this thesis, MIPs were synthesized using Q -methacrylic acid as functionalmonomers, ethylene glycol dimethacrylate as crosslinkef, azobisisobutyronitrile asinitiator and theophylline (THO) and caffeine (CAF) as template molecules. Factorsinfluencing polymerization were discussed. UV spectrophotometry was adopted toresearch the adsorption character and selective recognition ability of the MIPs. UsingTHO-MIPs as soIid phase extraction (SPE) packings, we testified its SPE totheophylline, factors infiuencing its performance were also discussed. Lastly, weextracted theophylline from tea solution using MIPs-SPE. Repeatability wasexamined by repeated experiments.The results showed that difference between polymerization conditions had fairlyinfluence on adsorption character and selective recognition ability of the MIPs. Theperformance of MIPs using theophylline as template is better than that of the onesusing caffeine as template; MDs with the ratio of functional monomer to template of4:l behave better than that of 2fl and 6:l; In addition, chloroform is better thanacetonitrile when used as porogen. Using THO-MIPs as solid phase extractionpackings, we found that choosing of washing so1vents, e1uting solvents and flow ratehad strong effects on extraction results. Theophylline in tea solutions were extractedby THO-MIPs, HPLC results showed that it can be preconcentrationed and eIutedeffective1y, the recovery is 84.3%. The packings showed good stability with therecovery of 79.8% after being used for l0 times.更多还原