Determination Of 47 Pesticides And Their Metabolites In Vegetables By Ultra Performance Liquid Chromatography Mass Spectrometry

Four pretreatment coupled with ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)methods were developed for the determination of 47 pesticides in vegetables,and of 42 pesticides can be determined simultaneously.Two extraction methods(Ori Qu Eextraction salt package and EN method extraction salt package)and two purification methods(Dis Qu E tube purification and raykol m-PFC column purification)were used in the pretreatment of lettuce,tomato and cucumber.The gradient elution of 0.1% formic acid and methanol,and the Thermo Hypersll GOLD C18 column.,Electrospray ionization positive ion mode(ESI+)and multiple reaction monitoring(MRM)were used to determine the content.The external standard method(matrix standard)was used to quantify.The results showed that the results of diflubenzuron,diflubenzuron,flufenuron,chlorfenuron and phoxim did not meet the requirements of GB /T27417-2017,so the method was not applicable.The results of methamidophos,chlorpyrifos and other 42 pesticides met the requirements of GB /T27417-2017.The limits of detection(LOD)and limits of quantitation(LOQ)were 0.01 ? 0.5 ?g / kg,0.1 ? 2.0 ? g / kg andthe average recoveries were 76.1% ? 88.9%with the relative standard deviatations from 0.8% ? 3.1% by using Ori Qu Eextraction,salt package and Dis Qu Epurification tube;The limits of detection(LOD)and limits of quantification(LOQ)were0.01 ? 0.5 ? g / kg and 0.1 ? 2.0 ? g / kg,and the average recoveries were 75.9% ? 88.9% with the relative standard deviatations from 1.1% ? 3.0% by using EN method extraction salt package and raykol m-PFC column purification.The limits of detection(LOD)and limits of quantification(LOQ)were 0.01 ? 0.5 ? g / kg and 0.1 ? 2.0 ? g / kgand the average recoveries were 76.1% ? 88.9% with the relative standard deviatations from 1.5% ? 2.8% by using Ori Qu Eorique extraction salt package and Dis Qu Edisque purification tube;The limits of detection(LOD)and limits of quantification(LOQ)were 0.01 ? 0.5 ? g / kg and 0.1 ? 2.0 ? g /kgand the average recoveries were 73.9% ? 87.5% with the relative standard deviatations from1.1% ? 3.0%.by using EN method extraction salt package and raykol m-PFC column purification.The results showed that the four pretreatment methods coupled with UPLC-MS /MS were suitable for the determination of a variety of pesticides and metabolites in vegetables,with the characteristics of simple,rapid,sensitivity and accuracy,which further expanded the detection technology of pesticide residues.