采用分子印迹检测生姜中甲胺磷的残留量

Determination of methamidophos in spiked ginger using molecularly imprinted technique

目的建立生姜中甲胺磷残留检测的分子印迹法。方法采用分子印迹-固相萃取的方法对生姜中甲胺磷进行分离富集,并结合液相色谱的方法进行定量。采用沉淀聚合方法合成甲胺磷印迹聚合物,以甲胺磷为模版、α-甲基丙烯酸为单体、三羟甲基丙烷三甲基丙烯酸酯为交联剂,摩尔比为1:8:40。结果静态吸附实验数据显示,吸附在10 min达到平衡,印迹聚合物对甲胺磷的吸附率高于80%,印迹因子是2.105,印迹聚合物的最大表观吸附量为3.24μmol/g。生姜汁加标实验的平均添加回收率高于86.4%,相对标准偏差低于4.5%(n=6)。结论该方法可用于生姜中甲胺磷的检测。

Objective To establish a method for the determination of methamidophos residue in spiked ginger by molecular imprinting method. Methods The methamidophos in ginger were isolated and enriched with the method of molecularly imprinted-solid phase extraction, and the method of liquid chromatography was used for quantitative analysis. The molecularly imprinted polymer（MIP） was synthesized by precipitation polymerization method while methamidophos was used as the template, α-methacrylic acid was monomer, and trimethyl-propane trimethacrylate was crosslinking agent, and their feeding molar ratio was 1：8：40. Results The static adsorption experiment data showed that the adsorption was balanced at 10 min. The adsorption rate of methamidophos was higher than 80%. The imprinting factor was 2.105, and the maximum apparent adsorption capacity of the imprinted polymer was 3.24 μmol/g. The average adding recovery rate of raw ginger juice was higher than 86.4%, and the relative standard deviation was less than 4.5%（n=6）. Conclusion This method can be used for the detection of methamidophos in spiked ginger containing sulfhydryl compounds.