液相色谱-串联质谱法检测植物源食品中 草甘膦及其代谢物的残留量

目的建立一种高效液相色谱-串联质谱测定植物源食品中草甘膦及其代谢物氨甲基膦酸残留量的分析方法。方法样品经水超声提取,用二氯甲烷去除脂肪,并用C18固相萃取小柱进行净化,以9-芴甲基氯甲酸酯(FMOC-Cl)进行衍生,最后采用高效液相色谱-串联质谱进行测定。结果对茶叶和其他植物源食品的检出限分别为0.1 mg/kg和0.02 mg/kg,在5~100 ng/m L线性范围内线性关系良好(r20.999)。草甘膦各浓度水平的平均回收率为74.6%~96.5%,相对标准偏差为0.041%~0.553%(n=6);氨甲基膦酸的平均回收率为65.1%~79.4%,相对标准偏差为0.024%~0.338%(n=6)。结论建立的方法快速简便,灵敏度较高,精密度较好,符合国家标准对植物源食品中农药残留测定的要求,可用于食品安全监管。

Determination of glyphosate and aminomethylphosphonic acid residues in plant-derived foodstuff by high performance liquid chromatography-tandem mass spectrometry

Objective To establish a method for the determination of glyphosate (PMG) and metabolite- aminomethylphosphonic acid (AMPA) residues in plant-derived foodstuff by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods After extracted with water under ultrasonication, the samples were defatted with dichloromethane and then purified by C18 solid phase extraction cartridge. The samples were derived with fluorenylmethylchloroformate (FMOC-Cl), then detected by HPLC-MS/MS. Results The limit of detection (LOD) of tea and other plant-derived foodstuffs were 0.1 mg/kg and 0.02 mg/kg, respectively. The calibration curves showed a good linearity in the range of 5~100 ng/mL with the correlation coefficient (r2) more than 0.999. The average spiked recoveries of PMG were range from 74.6% to 96.5% with the relative standard deviations (RSDs) between 0.041% and 0.553% (n=6). The average spiked recoveries of AMPA were between 65.1% and 79.4%, and the RSDs were range from 0.024% to 0.338% (n=6). Conclusion The method is simple, fast, sensitive and accurate and accord with China national standard for the detection pesticide residues in plant-derived foodstuff, which is suitable for the supervision of food safety.