QuEChERS-气相色谱-三重四级杆串联质谱法测定茶叶中的12种有机氯农药残留

Simultaneous determination of 12 kinds of organochlorine pesticide residues in tea by QuEChERS pretreatment method with gas chromatography-triple quadrupole tandem mass spectrometry

目的建立QuEChERS前处理结合气相色谱-三重四级杆串联质谱法(gas chromatography-triple quadrupole tandem mass spectrometry,GC-QqQ-MS/MS)用于茶叶中12种有机氯农药(α-六六六、β-六六六、γ-六六六、δ-六六六、五氯硝基苯、艾氏剂、狄氏剂、七氯、硫丹-I、硫丹-II、顺式-氯丹、反式-氯丹)残留的同时检测分析方法。方法样品经乙腈提取,醋酸钠、无水硫酸镁盐析,QuEChERS方法净化,浓缩后,经气相色谱-三重四级杆串联质谱仪采用多反应离子监测(multiple reaction monitoring,MRM)模式进行分析测定,外标法定量。结果 12种有机氯农药在0.005~0.1μg/mL范围内线性关系良好,线性相关系数(r^2)不小于0.9990;在0.01、0.04和0.1μg/mL 3个添加水平下,平均加标回收率为69.30%~97.02%;相对标准偏差(relative standard deviations,RSDs)为0.56%~9.27%(n=6)。12种有机氯农药的检出限均小于1μg/kg。结论该法样品处理快速简单,灵敏度高,适用于茶叶中有机氯农残检测工作。

Objective To establish an analytic method for the simultaneous determination of 12 kinds of organochlorine pesticide residues （α-BHC, β-BHC, γ-BHC, δ-BHC, pentachloronitrobenzene, aldrin, dieldrin, hcptachlor, endosulfan-I, cndosulfan-II, trans-chlordanc and cis-chlordane） in tea by QuEChERS pretreatment combined with gas chromatography-triple quadrupole tandem mass spectrometry （GC-QqQ-MS/MS）. Methods The samples were extracted with acetonitrile, followed by salting-out with sodium acetate and anhydrous magnesium sulfate, cleaned up with the method of QuEChERS and concentrated. Then they were analyzed in the mode of multiple reaction monitoring （MRM） by GC-QqQ-MS/MS and quantified by the external standard method. Results Totally 12 kinds of organochlorine pesticides had good linear relationships in the range of 0.005-0.1 μg/mL, and the linear correlation coefficients （r^2） were all not less than 0.9990. The average recoveries of all the organochlorine pesticides were 69.30%-97.02% at the three spiked levels of 0.01, 0.04 and 0.1 μg/mL, and the relative standard deviations （RSDs, n=6） were in the range of 0.56% to 9.27%. The limits of detection （LODs） of all the pesticides were below 1 μg/kg. Conclusion This method is rapid and simple and has high sensitivity, which is suitable for the determination of organochlorine pesticide residues in tea.