Determination of 41 pesticide residues in vegetables by QuEChERS-ultra performance liquid chromatography- tandem mass spectrometry

A multiresidue analytical method for the rapid determination of 41 pesticide residues in vegetables was developed by using QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), including recessive pesticides, banned pesticides and pesticides with restrict use, plant growth regulators and some other pesticides with high detection rates. The vegetable sample was extracted by 1% (v/v) acetic acid-acetonitrile, cleaned-up by primary secondary amine (PSA) and injected for analysis. The positive and negative ion modes and multiple reaction monitoring (MRM) mode were used in the analysis, and the analytes were quantified by the external standard method. Under the conditions of optimized QuEChERS, chromatography and mass spectrometry, the 41 pesticides showed good linearities in the range of 1.0 µg/L to 100 µg/L, with the correlation coefficients (r2) higher than 0.999. The limits of detection of the method were 0.003 µg/kg to 1.00 µg/kg. The average recoveries of the 41 pesticides in different matrices were in the range of 74.1%-120.4% with the relative standard deviations from 2.8% to 11.9%. The method has the advantages of rapidity, simplici- ty, high sensitivity and better purification effect. It is suitable for the rapid determination of the common pesticides in vegetables, and it provides a strong guarantee for the risk assessment of the quality and safety of vegetables.