Determination Of Carbamate Pesticides In Biological Samples By Liquid Chromatography-Tandem Mass Spectrometry With QuEChERS Method

Carbamate pesticides are widely used as insecticides,fungicides and herbicides in China.Poisoning,wrong consumption,suicide and other intoxication cases caused by such pesticides often occur,therefore the qualitative estimation and quantitative analysis of carbamate pesticides in biological samples have become an important issue for the inspection and identification in the sector of public security.The samples to be tested are mostly victims'biological samples,such as blood,urine and liver The matrix is complex and the interference components are many.The traditional pretreatment method is difficult to effectively purify.In this paper,a rapid,simple and sensitive detection method for carbamate pesticides in biological samples such as blood,urine and liver was established by using the improved QuEChERS?Quick,Easy,Cheap,Effective,Rugged,Safe?sample pretreatment method combined with ultra performance liquid chromatography-tandem mass spectrometry?UPLC-MS/MS?,in order to meet the needs of sector of public security to investigate and solve crimes.This paper contain the contents of the following five chapters.The first chapter mainly introduced the properties and harms of carbamate pesticides,the pretreatment and detection methods for carbamate pesticides in biological samples,the QuEChERS sample pretreatment method and the application in detecting pesticides in biological samples.The second chapter established the method of determination of five carbamate pesticides?methomyl,metolcarb,propoxur,carbaryl and isoprocarb?by ultra performance liquid chromatography-tandem mass spectrometry.The analytes were separated on a ZORBAX Eclipse Plus C₁₈ column?2.1 mm×100 mm,1.8?m?with 5 mmol/L ammonium acetate solution?containing 0.1%formic acid??A phase?and methanol?B phase?gradient elution in electrospray ion source positive ion?ESI⁺?scan mode ionization,multiple reaction monitoring?MRM?mode detection.In the third chapter,the QuEChERS method for whole blood samples was optimized.The extraction agent,the salting-out agent and their dosages during the pre-processing of a whole blood sample as well as the dosages of PSA and C₁₈ and the oscillation duration during the purification process were optimized.Using the optimized QuEChERS method,the linearity of the five carbamate pesticides in the concentration range was good?R²>0.996?,the detection limit was 0.1-0.5 ng/mL and the quantification limit was 0.5-0.75 ng/mL.At the three spike levels,the recovery was 88.6%to 102.6%,and the inter-day precision and intra-day precision were equal to or less than 8.2%.The method is simple,fast,efficient and reliable,which is suitable for the inspection of carbamate pesticides in whole blood samples.In the fourth chapter,the QuEChERS method for urine samples was optimized.The extraction agent,adsorbent agent and their dosages during the pre-processing of a urine sample were optimized.The optimized QuEChERS method did not use a salting-out agent.Using the optimized QuEChERS method,the linearity of the five carbamate pesticides in the concentration range was good?R²>0.997?,the detection limit was 0.1-0.5 ng/mL and the quantification limit was 0.5-0.75 ng/mL.Under the level of three standards addition,the recovery was 93.2%to 113.2%,and the inter-day precision and intra-day precision were equal to or less than 10.0%.The method is simple,fast,efficient and reliable,which is suitable for the inspection of carbamate pesticides in urine samples.In the fifth chapter,the QuEChERS method for liver samples was optimized.The extraction agent,salting-out agent,adsorbent agent and their dosages during the pre-processing of a liver sample were optimized.Using the optimized QuEChERS method,the linearity of the five carbamate pesticides in the concentration range was good?R²>0.996?,the detection limit was 0.1-0.2?g/kg and the quantification limit was 0.25-0.5?g/kg.At the three spike levels,the recovery was 70.6%to 110.2%,and the inter-day precision and intra-day precision were equal to or less than 12.1%.The method is simple,fast,efficient and reliable,which is suitable for the inspection of carbamate pesticides in liver samples.