虚拟分子印迹固相萃取技术检测食品中10种三嗪类除草剂残留

摘要

The molecularly imprinted polymers (MIPs) capable of extracting triazines from food samples were prepared by suspension polymerization using butylmelamine (BME) as template, methacrylic acid (MAA) as monomer and ethylene glycol dimethacrylate (EDMA) as cross-linker, respectively. Molecular modeling approach was used to screen the most suitable dummy template. The selective adsorption of MIPs was evaluated by high performance liquid chromatography. The synthesized MIPs were used as the solid phase extraction (SPE) materials. The optimum loading, washing and eluting conditions for molecularly imprinted solid phase extraction (MISPE) were established to obtain high selectivity and sensitivity. Compared with commercial SPE columns, MISPE exhibited selective binding properties for triazines, and the matrix effect was significantly decreased. The recoveries of all 10 triazines in matrix spiked samples were ranged from 87. 8% to 105.2%, with the relative standard deviations (RSD) below 13% (n = 6).%以正丁基三聚氰胺为虚拟模板,α-甲基丙烯酸为功能单体,乙二醇二(甲基丙烯酸)酯为交联剂,采用悬浮聚合法制备得到对三嗪类除草剂具有高选择性的分子印迹聚合物.运用分子模拟技术探讨了虚拟模板的筛选方法；利用高效液相色谱法考察了印迹聚合物对三嗪类除草剂的选择吸附性；以此聚合物作为固相萃取填料,研究了分离、富集食品中三嗪类除草剂的最佳萃取条件.与其它固相萃取柱相比,所制备的分子印迹固相萃取柱对三嗪类除草剂有较好的分子识别能力,能有效降低基质效应.基质加标三嗪类除草剂回收率为87.8％～105.2％；相对标准偏差(RSD)均小于13％(n=6).