QuEChERS-超高效液相色谱-串联质谱法测定茶叶中3种杀虫剂手性农药

Determination of 3 kinds of chiral pesticides in tea by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry

中文关键词:  QuEChERS  超高效液相色谱-串联质谱法  手性杀虫剂  茶叶

英文关键词:QuEChERS  ultra performance liquid chromatography-tandem mass spectrometry  chiral insecticide  tea

中文摘要:

      目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定普洱茶(晒青毛茶和普洱熟茶)中呋虫胺、水胺硫磷、茚虫威等3种手性杀虫剂对映异构体的分析方法。方法 采用1%乙酸的乙腈作为提取溶剂, N-丙基乙二胺(primary secondary amine, PSA)混合石墨化碳黑(carb)净化, 经Chiralpak IG手性柱分离, UPLC-MS/MS测定, 基质外标法标定量。结果 3种农药的在0.002~0.2 mg/L线性良好, 相关系数(r)均大于0.993, 定量限(limits of quantification, LOQ)为0.0025~0.25 mg/kg。晒青毛茶和普洱茶中3个添加水平(0.025、0.05和0.5 mg/kg)的平均回收率为73.57%～123.7%, 相对标准偏差(relative standard deviation, RSD) (n=6)在2.6%～18.7%之间。结论 该方法操作简便、准确度高、成本低, 可以用于测定普洱茶中3种手性杀虫剂农药残留。

英文摘要:

      Objective To establish a method for the determination of isomers of 3 kinds of chiral pesticides (dinotefuran, isocarbophos, indoxacarb) of in sun-dried green tea and Pu’er ripe tea by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods 1% acetic acid in acetonitrile was used as the extraction solvent for samples, and the purified process was mixed primary secondary amine with carb purification The extracts were separated by Chiralpak IG chiral column, detected by UPLC-MS/MS and quantified by matrix external standard method. Results Three kinds of pesticides had good linearity from 0.002 to 0.2 mg/L, the correlation coefficient was greater than 0.993, and the limits of quantification were from 0.0025 to 0.25 mg/kg. The average recoveries of 3 kinds of additive levels were 73.57% to 123.7% in dried green hair tea and Pu’er tea, and the relative standard deviation was 2.6% to 18.7% (n=6). Conclusion This method is simple to operate, high accuracy, and low cost, which can be used to determine the residues of 3 chiral pesticides in sun-dried green tea and Pu’er tea.