超高效液相色谱-串联飞行时间质谱法测定绿茶中9种拟除虫菊酯类农药

Determination of nine pyrethroids in green tea by ultra high performance liquid chromatogram tandem time of flight mass spectrometry

中文关键词:  拟除虫菊酯  超高效液相色谱串联飞行时间质谱  裂解规律

英文关键词:pyrethroids  ultra high performance liquid chromatography tandem time-of-flight mass spectrometry  fragmentation pathway

中文摘要:

      目的 建立绿茶中9种拟除虫菊酯农药残留量检测的方法。方法 采用超高效液相色谱电喷雾串联飞行质谱对9种拟除虫菊酯进行定量和裂解途径研究。结果 样品经QuEChERS方法处理后上机, 正离子模式下氟氯氰菊酯、氯氰菊酯、溴氰菊酯、氰戊菊酯、氟氰戊菊酯、四溴菊酯易形成[M+NH4]+加合离子, 苯醚氰菊酯、甲氰菊酯、氟胺氰菊酯易形成[M+H]+加合离子。采用一级母离子定量, 9种拟除虫菊酯1~20 μg/L范围内线性关系良好(r2>0.99); 9种拟除虫菊酯的最低检出限均为1 μg/kg; 2~10 μg/kg范围内回收率为85.2%~106.3%; 相对标准偏差(RSD)≤6.1%。结论 方法简便、高效适用于绿茶中拟除虫菊酯类农药残留的快速筛查。

英文摘要:

      Objective To establish a method for the determination of pesticide residues of 9 pyrethrins in green tea. Methods Ultra high performance liquid chromatography electrospray ionization quadrupole-time-of-flight mass spectrometry was used for the quantification and fragmentation pathway of 9 pyrethroids. Results After extracting pyrethroids by QuEChERS method, the samples were easy to form [M+NH4]+ adduct ions under the positive ion mode, while [M+H]+ adduct ion were easy to form under the positive ion mode. The linear relationship of the method were significant within the range of 1~20 μg/L(r2>0.99). The limits of detection of all the 9 pyrethroids were 1 μg/kg. The recoveries within the range of 2~10 μg/kg were 85.2~106.3%, and relative standard deviations (RSD) was no less than 6.1%. Quasi-molecular ions of 9 pyrethroids were fragmented from either ammonium adducts or hydrogenated molecules. Conclusion The method is simple and efficient for the rapid screening of pyrethroid pesticide residues in green tea.