The Analysis And Determination Of The Veterinary Drug Residues In Animal Tissues

The veterinary drug residues in food has become a weighty and disputed problem in recent years since it is close to public health and has greatly affected the economic benefits of the animal husbandry. The residue level of the veterinary drug residues is nearly 1 μg ~1mg in the food or lower, and there are many interference factors while measuring, so it is extremely necessary and urgent to develop convenient and high-efficient previous treatment method , and the high sensitivity and alternative detection method.This dissertation consists of three parts. The first chapter summarized the progress of veterinary drug residues analysis in animal tissue. Chapter two is the study and application of GC method by which analyzes Clenbuterol(CL) in the animal tissue. The third, four, five chapters adopt different detection methods for determining free gossypol in animal sample respectively. The details are as following:The first chapter mainly introduces some commonly used sample preparation methods and their applications in the analysis of veterinary drug residues. These methods include Sonication-assisted Extraction(SAE), Solid Phase Extraction(SPE), Matrix solid-phase dispersion(MSPD), Supercritical Fluid Extraction(SFE).The regulatory analysis methods such as gas chromatography(GC), high performance liquid chromatography(HPLC) and immunoanalysis(IA) are briefly summarized and the purpose and meaning of the research in this paper are given finally.Chapter 2 describes an analytical method for CL in animal tissues by GC with electron capture detector(ECD) directly. The CL was extracted with hydrochloric acid and purified by C18 SPE column packed, then derivatization with BSTFA. At last CL was carried out by capillary gas chromatography with GC-ECD. The minimum detectable quantity is 1.0 μg/kg. The result is accurate proved by the analytical methodology and can be regarded as screening detection method for Clenbuterol in animal tissues.Finally, we applied this method to survey report which was about CL residues of animal tissues in Urumqi and surrounding area, and got satisfying results.In the third chapter, a method for analysis of Free Gossypol(FG) in animal tissues by HPLC with diode array detector(DAD) was proposed. FG was extracted with a mixture of acetone and water(70:30,v/v) and was concentrate through rotating the evaporation. The analyses were carried out by BDS HYPERSIL C18 (250*4.6mm i.d.5 μm) column with HPLC-DAD. The method was quantified by an external standard mode. The detection limits of the method was 0.1mg/kg, recovery is in the range of 81.4% ~ 101.8%, the relatively standard deviation(RSD) is 1.6% ~10.5%. The result of test coincided with the request of analyzing drug residues.The fourth chapter reported preliminary study of detecting FG in animal tissues with previous-column derivatization by HPLC. Combining sample extraction with derivatization and building strong UV absorption groups in the structures of onmeasuring molecules so as to increase the sensitivity of the detection. Calculating by sample added and retrieving experiment, the recovery of method is 60.6%, RSD is 8.2~14.5%,the detection limit of the method is 0.02mg/kg, the result is satisfied.In the fifth chapter, a HPLC-MS method is presented for FG in the animal tissue. The steps for FG extraction and purification are similar with those in Chapter 3 after getting rid of the water from the animal tissue. The mass spectrum adopts the electrospray ionization(ESI) as ion source and quantitative detection was carried out using the selected ion monitoring(SIM) mode. Choosing 517as mass charge rate of the ion measure. The detection limit of the method is 0.5 μg/L. The average recovery is 79.7%, RSD is 2.2~16.2%, and the result accorded with the request of the world trace analyst of remaining regulation Committee.