QuEChERS结合GC-MS/MS法测定24批次桔梗中34种农药残留

Determination of 34 Pesticide Residues in 24 Batches of Platycodonis Radix Using QuEChERS Combined With GC-MS/MS

建立基于QuEChERS法结合气相色谱-串联质谱法(GC-MS/MS)对桔梗中34种农药残留量的快速检测方法,并应用于24批桔梗样品筛查。采用QuEChERS法对样品进行前处理,在气相色谱-串联质谱多反应监测(MRM)模式下进行测定,考察其线性关系、定量限、回收率和精密度。以所建立的方法对24批桔梗样品中34种农药残留进行测定分析。34种农药在一定质量浓度范围内线性关系良好,相关系数r均>0.998,其LOQ在0.0003~0.6000 mg/kg之间;回收率均在60%~130%范围内,RSD均<15%。有18批次桔梗样品检出农药残留,检出率为75%;检出农药对硫磷、甲基异柳磷、治螟磷、三氯杀螨醇、氟虫腈,其含量均在0.001~0.015 mg/kg之间,低于药典规定的0.02 mg/kg的限度,所检样品合格率为100%;其余农药未检出。所建立的QuEChERS法结合气相色谱-串联质谱法可用于桔梗中34种农药残留物的定性定量分析,可为桔梗的质量管控提供技术支撑。

This study aimed to establish a method for the simultaneous determination of 34 pesticide residues in Platycodonis Radix using QuEChERS and GC-MS/MS.The method was applied to screen 24 batches of sample.The samples were prepared using QuEChERS method and then analyzed by GC-MS/MS in multiple-reaction monitoring(MRM)model.The linearity,limit of quantitation(LOQ),recovery rate,and precision was investigated under the specified analysis conditions.34 pesticide residues in 24 batches sample of Platycodonis Radix were detected by this method.The linear relationship of each pesticide residue showed a good linearity within a certain range of mass concentration,with correlation coefficient above 0.998.The LOQ values ranged from 0.0003 and 0.6000 mg/kg.The recovery rate were between 60%and 130%,with RSD not exceeding 15%.Pesticide residues were detected in 18 batches of Platycodonis Radix samples,resulting in a detection rate of 75%.However,Parathion,Isofenphos-methyl,sulfotep,fipronil and dicofol were found to be below the limits of 0.02 mg/kg specified in the Chinese pharmacopoeia,with contents ranging from 0.001~0.015 mg/kg.Therefore,the qualified rate for all samples was 100%.The QuEChERS methods combined with GC-MS/MS proved effective for qualitative and quantitative analysis of 34 pesticide residues in Platycodonis Radix,providing valuable technical support for quality control of Platycodonis Radix.