Study On Detection Of Multi-Pesticide Residues And Mycotoxins In Wine By UHPLC-MS/MS And Based On QuEChERS Extraction

In recent years,with the increasing consumption of wine,people pay more and more attention to the safety of wine.The two most common pollutants in wine are pesticide residues and mycotoxins,both of which are harmful to human health.Therefore,it is necessary to develop a rapid method for simultaneous detection of multi-pesticide residues and mycotoxins in wine.In recent years,liquid chromatography-mass spectrometry has been widely used for simultaneous detection of multiple substances,and it has high sensitivity and specificity.QuEChERS is one of the fastest developing method in pretreatment technologies.It has fewer extraction steps,simple and safe operation,as well as economically and environmentally friendly.Therefore,based on QuEChERS method,this experiment optimized and validated the pretreatment methods of various pesticide residues and mycotoxins in wine,and develop an instrument method for simultaneous detection by liquid chromatography-mass spectrometry.The results are as follows:(1)UHPLC-MS/MS instrumental detection method was developed and optimized.Multi-reaction monitoring(MRM)mode was adopted and ESI positive source was used.10mmol/L ammonium acetate solution(0.2%formic acid)was used as mobile phase A and acetonitrile as mobile phase B.Optimum mass spectrometric parameters such as precursor ion,product ions,fragment ion,and collision energy were selected.All target compounds responded well.(2)The acidity of the extracting solvent was optimized.1%formic acid-acetonitrile solution was selected as the extracting solvent,and the purification step of the dispersed solid phase extraction agent was omitted.UHPLC-MS/MS(ESI positive mode)detection was carried out directly after drying with anhydrous magnesium sulfate.The extraction efficiency was high.(3)The linear correlation of 66 target compounds was good in the concentration range of0.05-500.00?g/kg,R~2 was not less than 0.9935,LOD was 0.05-20.00?g/kg.For the majority of pesticide residues and mycotoxins,the accuracy and precision of this method are good(<11%).The recovery of standard addition is 68.46-118.51%at three different concentration levels,and RSD is between 1.06-10.01%,which meets the detection requirements.(4)64 wines from Hexi Corridor of Gansu Province,foreign wineries and laboratory brewing in different years from 2008 to 2017 were detected by the developed method.The results showed that 24 pesticide residues such as azoxystrobin dimethomorph,haloxyfop-methyl,and 4 mycotoxins such as deoxynivalenol and fumonisin B1 were detected,among which fumonisin B1 was the highest(103.63?g/kg).The most commonly detected pesticide residues in wine are dimethomorph,haloxyfop-methyl,and metalaxyl.There are also some pesticide residues with low frequency,such as boscalid,thiophanate-methyl,etc.