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(R2>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 ( R2 ) 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.
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