Study On Sample Preparation Techniques For Analysis Of Veterinary Drug Residues In Agricultural Products

As unsafe food hazard events occur frequently, People take more attention to the quality and safety of foodstuffs. And food safety problems have been regarded as national public security around the world, each country stepping up the supervision In recent years, people took more attention in kinds of chronic, chemicals, drug resistance problems which caused by longterm intake of veterinary drug residues. Therefore, it is significant to establish quick, easy and low cost sample preparation methods for determination of veterinary drug residues in foodstuffs. In this thesis, the technology based on high performance liquid chromatography tandem mass spectrometry for detecting a few kinds of veterinary drug residue was developed. The thesis includes four chapters.In the first chapter, the contents included some kinds of antibiotics in animal origin food. Then, the sample preparation and pretreatment techniques of drug residues in food analysis were briefly introduced. The analysis and detection technology of drug residues in foodstuffs was generally described. Finally, the study pointed out the purpose and main content of this thesis.In the second chapter, a method of molecularly imprinted solid phase extraction coupled with UPLC/MS/MS was developed for detecting malachite green (MG), crystal violet (CV) and their metabolites leucomalachite green (LMG), leucocrystal violet (LCV) in sea eel.The influences of liquid extraction agent, solid extraction agent, the filler of solid phase extraction column, the quality of filler and elution solvent were studied in detail. Under optimum condition, the method showed a good linearity in the range of 0.1-10 μg/L for four targets, correlation coefficients were between 0.9982 and 0.9991. The LOD of malachite green (MG) and CV were 0.03μg/kg, the LOD of other targets were 0.02μg/kg, the relative standard deviation (RSD) of the method was beteen 2.78% and 5.69%.2.78%-5.69%In the third chapter, a method of simultaneous detecting eight glucocorticoids residues in chicken tissues by ultra performance liquid chromatography-electrospray tandem mass spectrometry was developed. The influences of instrument condition, extraction solvent and cleaning solvent were studied in detail. Under optimum condition, the method showed a good Linearity in the range of 0.5 μg/kg～20μg/kg for prednisone while the other targets were 0.1 μg/kg-20 μg/kg, the recoveries in chicken meat were 70%～101% in the standard addition levels form 0.5μg/kg to 20μg/kg, the relative standard deviation (RSD) of the method was beteen 1.54% and 12.47%. The method was also suitable for milk and pork liver samples.In the forth chapter, a method of detecting amantadine residues in chicken tissues by Liquid chromatography-electrospray ionization tandem mass spectrometry was developed. The limits of detection of amantadine residues were 1.0～4.0 μg/kg and with a linear range from 0.1 to 100 μg/L. Three concentration levels of 2μg/kg、4 μg/kg and 10μg/kg were spiked in chicken tissues, and overall recoveries were between 86.0% and 109.2% with the relative standard deviations (RSDs) between 2.7% and 10.5%. The real sample test showed that this method could be used for sensitive and accurate determination of amantadine residues in chicken tissues.