Detection Of Pesticide Residues In Fruits And Vegetables Based On QuEChERS Method Combined With UPLC-MS/MS And GC-MS/MS

Pesticide residue is an important indicator to measure the level of food safety,and it is an important chemical hazard factor in food safety.The food safety situation in recent years has received increasing attention from government regulatory agencies and consumers.Monitor the use of pesticides in fruits,vegetables,grain,oil,and tea,monitor residue levels,protect the health of our people from pesticide residues,and vigorously carry out pesticide residue detection technologies,especially multi-residue detection technologies.It is necessary to develop and improve the pre-processing technology.Since its introduction in 2003,QuEChERS?Quick,Easy,Cheap,Effective,Rugged and Safe?technology has brought unprecedented renewal in the field of pesticide multi-residue analysis and multiple types of pesticide detection.The previous pretreatment technology has undergone several processes including liquid-solid extraction,liquid-liquid extraction and solid-phase extraction.Summing up the previous pretreatment methods,a chemist of the US Department of Agriculture developed a method for trace analysis of pesticide residues in fruits and vegetables in 2003.Based on the QuEChERS method,rapid detection technology for rapid detection of multiple pesticides has developed rapidly thanks to the high sensitivity and selectivity of liquid chromatography tandem mass spectrometry and gas chromatography tandem mass spectrometry.At present,QuEChERS has been widely used in the detection of fruits and vegetables and its products around the world.With the continuous development of technology,QuEChERS is also gradually applied to other fields such as meat,wine,soil,and medicine.Based on triple quadrupole tandem mass spectrometry,the present study was conducted on an Ultra Performance Liquid Chromatography?UPLC-MS/MS?and a Gas chromatography-tandem mass spectrometery.GC-MS/MS)for selective combination.Optimize the QuEchERS pre-processing technology,collect high-risk pesticide residue projects at home and abroad,and early-warning projects in China,combine domestic sampling inspection and unqualified projects,and establish a high-risk pesticide multi-residue rapid analysis method that meets domestic and international monitoring requirements.And innovations are as follows:?1?Using potato as raw material,the original QuEChERS pretreatment method was improved,and six representative pesticides were selected to optimize the purification conditions.In the experiment,the Primary and secondary amine?PSA?and Gel Permeation chromatography?GCB?was finally used.The extraction combination was determined to be0.1%acetonitrile in 15 m L,anhydrous MgSO₄ in 6 g,and NaAc.3H₂O in 2.5 g.The purification combination was PSA 500 mg,anhydrous MgSO₄ 1.5 g,and GCB 100 mg.?2?.The difference between the addition of the analytical protection agent compared to the conventional method was studied.By comparison of chromatograms,the addition of an analytical protectant can effectively overcome the effects of matrix effects on the target and the effect of active sites on the target in the instrument system,increase the sensitivity of the target,and improve the peak shape and stability of the target.?3?.According to the nature of pesticides,determine the most suitable detection equipment for various pesticides and establish the best instrument parameters for 178pesticides.Due to the different types and properties of pesticides,some pesticides are easily gasified and suitable for gas chromatography analysis.Some pesticides are difficult to gasify and are suitable for liquid chromatography analysis.Through the research,74QuEChERS-GC-MS/MS detection methods for multi-residues of 74 pesticides in vegetables and QuEChERS-UPLC-MS/MS detection methods for 104 pesticides with multiple residues were established.?4?.Using the established method for multi-residue detection of pesticides in fruits and vegetables,the recoveries of samples from potatoes,carrots,apples,and spinach 4 were measured.The recoveries of 178 pesticides at the level of 0.02 mg/kg were in the range of71.3-118.6%.The relative standard deviation is less than 9.9%.Based on QuEChERS method combined with UPLC/MS/MS and GC/MS/MS to detect pesticide residues in fruits and vegetables,satisfactory results were obtained.The method uses less reagents,is environment-friendly,uses less space and appliances at the same time,has lower requirements for operators,and is simple and quick to operate.Each index satisfies accurate quantitative requirements.Compared with traditional detection technologies,the technology not only satisfies Market development requirements,but also has a good market competitiveness.In the further study,based on this method,we can continue to optimize the extraction and purification combination,expand the scope of the matrix,increase the number of testing items,and better serve the detection of pesticide residues in fruits and vegetables to improve food safety protection capabilities.