超高效液相色谱-串联质谱法测定不同茶叶中草甘膦、氨甲基膦酸及草铵膦的残留

Determination of Glyphosate,Aminomethyl Phosphonic Acid and Glufosinate in Different Teas by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

建立了超高效液相色谱-串联质谱同时快速测定不同茶叶中草甘膦、氨甲基膦酸及草铵膦的方法。样品用0.05 mol/L NaOH提取,并以HCl调节pH值, Oasis HLB小柱净化除杂,氯甲酸-9-芴基甲酯（ FMOC-Cl）柱前衍生反应后,超高效液相色谱-串联质谱法测定。本方法在5~1000μg/L浓度范围内,不同茶叶基质中草甘膦、氨甲基膦酸、草铵膦线性关系良好（R^2〉0.99）。在0.1,0.4和4 mg/kg添加水平下,不同茶叶（绿茶、红茶、乌龙茶、普洱茶）中3种化合物回收率均介于72.1%~109.9%之间,相对标准偏差RSD在0.5%~9.8%之间（n=6）,方法定量限（LOQ）在0.03~0.08 mg/kg之间（S/N=10）。本方法稳定,简便,灵敏,能够满足检测需求。

An efficient technique for the determination of multiclass pesticide residues （ glyphosate, aminomethyl phosphonic acid （ AMPA） and glufosinate） in four kinds of tea （ green tea, black tea, Oolong tea and Puer tea） was developed based on ultra performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Samples were extracted with 0. 05 mol/L NaOH solution, regulated pH value with HCl, followed by purification by Oasis HLB column, and then precolumn-derived with 9-fluorenylmethyl chloroformate （ FMOC-CL ） in borate buffer. All pesticide residues studied showed good linearity with correlation coefficient （ R^2 ） greater than 0. 99 in the concentration range of 5-1000 μg/L. Limits of quantitation （LOQs） of three pesticide compounds ranged from 0. 03 to 0. 08 mg/kg （S/N=10）. Tea samples spiked with 0 . 1 , 0 . 4 and 4 mg/kg showed the recovery ranging from 72 . 1% to 109 . 9%, and RSDs from 0. 5% to 9. 8% （n=6）. In addition, the validated method was applied to commercial samples, and all the detections were confirmed by acquiring transitions for each pesticide in samples.