Abstract:

A bi-templates molecularly imprinted polymers (MIPs) was prepared by using tebuconazole (TBZ) and triadimefon (TDF) as co-templates, methacrylic acid (MAA) as the functional monomer, and ethylene glycol dimethacrylate (EGDMA) as the crosslinker with the molar ratio of templates to MAA and EGDMA of 1∶4∶20. The adsorption kinetics, static adsorption, and affinity site characteristics and selectivity of the MIPs were investigated. The results showed that the adsorption equilibrium of dynamic adsorption was reached within 2.5 hours, implying a rapid adsorption kinetics. Scatchard analysis indicated that there were two types of affinity sites in the MIPs, and the MIPs had a good group and specific selectivity for triazole fungicides. A molecularly imprinted solid phase extraction column (MISPE) was prepared with the MIPs as fillers for tobacco sample pretreatment, and MISPE-ultra-high performance liquid chromatography-tandem mass spectrometry method was established for detecting residues of tebuconazole, triadimefon, myclobutanol and triadimenol in tobacco leaves. The results showed that the MISPE column had good enrichment effect on tebuconazole, triadimefon, myclobutanol and triadimenol. The average recoveries were between 72% and 110.3%, and the relative standard deviations (RSD) were 2.38%—7.92%, (n=3). The method can easily and selectively realize accurate analysis of triazole fungicides residues in tobacco leaves.

Key words: tebuconazole, triadimefon, bi-template, molecularly imprinted polymer, solid phase extraction, pesticide residue, adsorption

摘要：

以戊唑醇（TBZ）和三唑酮（TDF）为双模板分子，甲基丙烯酸（MAA）为功能单体，乙二醇二甲基丙烯酸酯（EGDMA）为交联剂，按摩尔比为1∶4∶20制备了戊唑醇-三唑酮双模板分子印迹聚合物（MIPs）。考察了MIPs的吸附动力学、静态吸附及亲和位点特征和选择识别性能。结果表明，MIPs可在2.5h内达到吸附平衡，Scatchard分析得出MIPs存在高低两类亲和位点，且具有良好的组选择性和特异选择性。以MIPs作为固相萃取填料，制备分子印迹固相萃取柱（MISPE）用于烟叶样品前处理，并建立MISPE-超高效液相色谱-串联质谱法检测烟叶中（戊唑醇、三唑酮、腈菌唑和三唑醇）残留的方法。结果显示，MISPE柱对戊唑醇、三唑酮、腈菌唑和三唑醇的富集效果较好，平均回收率为72%~110.3%，相对标准偏差在2.38%~7.92%（n=3）。该方法简单、选择性高，可实现对烟叶中三唑类杀菌剂残留的准确分析。

关键词: 戊唑醇, 三唑酮, 双模板, 分子印迹聚合物, 固相萃取, 农药残留, 吸附