基于GC-MS/MS的40种农药检测方法优化及蔬菜基质筛选的研究

Optimization of Detection Methods for 40 Pesticides Based on GC-MS/MSand Screening of Vegetable Substrates

目的:利用气相色谱串联质谱(Gas Chromatography-Mass Spectrometry,GC-MS/MS)测定蔬菜中农药残留量时,基质效应对定量结果影响大,通过探究10种蔬菜基质中40种待测物的基质效应,尝试找到一类代表性基质,兼顾检测准确度和工作效率。方法:根据仪器实际情况,优化气相色谱和质谱条件,建立40种农残GC-MS/MS同时测定方法;并对空白溶剂和10种基质中40种农残待测物的峰响应和回收率进行比对和分析。结果:GC-MS/MS在同批次测定多种类农产品时,辣椒、韭菜、豇豆可作为标准校正曲线的配制基质,基质影响韭菜最明显;豇豆次之;辣椒最不明显。但是在使用韭菜基质作为标准曲线校正时需要注意样品假阴性的情况。结论:GC-MS/MS法检测蔬菜中农药残留时,从10种基质中选择豇豆作为标准曲线配制的蔬菜基质,能够有效提高准确度和工作效率。

Objective:When determining pesticide residues in vegetables by gas chromatography mass spectrometry(GC-MS/MS),the matrix effect has a great influence on the quantitative results.By exploring the matrix effect of 40 substances in 10 vegetable substrates,trying to find a representative substrate,taking into account the detection accuracy and work efficiency.Methods:According to the actual situation of the instrument,the conditions of gas chromatography and mass spectrometry were optimized,and 40 kinds of GC-MS/MS methods for the simultaneous determination of pesticide residues were established.The peak responses and recoveries of 40 pesticide residues in the blank solvent and 10 matrices were compared and analyzed.Results:When GC-MS/MS is used to determine many kinds of agricultural products in the sample,batch,pepper,leek and cowpea can be used as the preparation matrix of the standard correction curve.The matrix affects leek>cowpea>pepper.However,when using leek matrix as the standard curve for calibration,it is necessary to pay attention to the false negative of the sample.Conclusion:When detecting pesticide residues in vegetables by GC-MS/MS method,cowpea was selected from 10 substrates as vegetable substrate prepared by standard curve,which can effectively improve the accuracy and efficiency.