QuEChERS/超高效液相色谱-串联质谱法测定茶叶中28种农药残留

建立了QuEChERS/超高效液相色谱-串联质谱（UPLC-MS/MS）测定绿茶中28种农药残留的分析方法。样品经1%乙酸乙腈提取，QuEChERS方法净化后进行UPLC-MS/MS测定。采用电喷雾离子源（ESI），正离子模式扫描，多反应检测（MRM）模式采集，基质匹配工作曲线法定量。结果表明:28种目标化合物在各自浓度范围内线性良好，相关系数（r）为0.990~0.998，检出限（LOD，S/N≥3）为0.08~1.26 μg/kg，定量限（LOQ，S/N≥10）为0.28~4.20 μg/kg；在10、50、80 μg/kg 3个加标水平下平均回收率为72.5%~118.5%，相对标准偏差（n=6）为0.8%~16.3%。该方法简单、快速、重现性好、稳定性高，可满足茶叶中28种农药残留的检测要求。

Determination of 28 Kinds of Pesticide Residues in Tea by QuEChERS/Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

A QuEChERS/ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)method was developed for the determination of 28 kinds pesticide residues in green tea.The tested samples were extracted with 1%glacial acetic acid acetonitrile,and then purified using QuEChERS method.Analysis on the targets was performed by electrospray ionization mass spectrometry in positive mode,multiple reaction monitoring(MRM)mode was used for collection,and matrix matched standard curve method was selected for quantitation.Results showed that 28 analytes showed good linearities in their respective ranges,with correlation coefficients(r)between 0.990 and 0.998.The limits of detection(LOD,S/N≥3)were 0.08~1.26μg/kg while the limits of quantitation(LOQ,S/N≥10)were 0.28~4.20μg/kg.Recoveries for the target analytes at spiked levels of 10,50 and 80μg/kg ranged from 72.5%to 118.5%,with relative standard deviations(n=6)of 0.8%~16.3%.The method is simple,rapid,replicable and high stable,and can satisfy meet the requirements for determination of 28 pesticide residues in tea.