Study On The Determination Method Of Sulfonamides And Chloramphenicols Veterinary Drug Residues In Aquatic Products

Nowadays, people need more animal origin foodstuffs everyday, so the residues of veterinary drugs in our foods become one of the most noticeable problems for security, which causes acute or chronic disease to public health, and bacteria tolerance to the drug, also causes many potential harm indirectly to health by circumstance and food chain. More and more researchers are studying on the determination of veterinary drug residues. We also need to develop some simple, sensitive and exact methods.In this paper, Eels, Longsnout catfish, langouste are the analytical objects and we research the determination of Sulfonamides, Thiamphenicol, Florfenicol residues in the aquatic products. The thesis consists of four parts. The details are as follwing:In Chapter One: Introduced the harm of Sulfonamides, Thiamphenicol, Florfenicol residues, summarized progress on analytical method of Sulfonamides and some other veterinary drugs. The determination of the residues of veterinary drugs usually contains two processes: sample pretreatment and detection. Sample pretreatment is very important to the result. It contains extraction and cleaned-up. There are many methods extracting the drugs from the sample, for example, homogenization, shaking, Soxhlet extraction, sonication-assisted extraction, supercritical fluid extraction, accelerated-solvent, microwave-assisted extraction, and so on. Cleaned-up contains liquid-liquid extraction, solid-phase extraction, Solid phase microextraction, Immunoaffinity chromatography, Gel permeation chromatography, and so on. At present, many methods have been reported in the literature for the determination of the residues in animal tissues. Such as high performance liquid chromatography, gas chromatography, chromatography-mass spectrometry, thin layer chromatography.In Chapter Two: A high performance liquid chromatographic method has been developed for the simultaneous determination of thirteen Sulfonamides residues in aquatic products (Eels, Longsnout catfish, langouste) . The samples were extracted with acetonitrile, and then cleaned up by n-hexane liquid-liquid extraction and solid phase extraction. The residues were determined by high performance liquid chromatography with ultraviolet detection and quantified by external standard method. The detection limits were 0.02mg/kg for sulfamethazine, sulfameter, sulfamonomethoxine, sulfachloropyridazine, sulfamethoxazole, sulfisoxazole, sulfadimethoxine, sulfaquinoxaline, and 0.05mg/kg for sulfadiazine, sulfapyridine, sulfathiazole, sulfamerazine, sulfamethizole. The linear ranges were 0.1μg/mL～5.0μg/mL. The average recoveries in spiked sample were 62%～97%.In Chapter Three: An Ultra performance liquid chromatographic method (UPLC) has been developed for the determination of Thiamphenicol, Florfenicol residues in aquatic products. The samples were extracted with ethyl acetate, next, cleaned up by n-hexane liquid-liquid extraction , The underlayer was applied to HLB SPE column . The cartridge was washed with 3mL 10% methanol. The residues were eluted from the cartridge with 5mL methanol. The eluate was evaporated to dryness under nitrogen stream, and then dissolved in 1mL 10% acetonitrile. The residues were determined by Ultra performance liquid chromatography with PDA detection and quantified by external standard method. The linear ranges were 0.05μg/mL～2μg/mL for Thiamphenicol and 0.025μg/mL～1μg/mL for Florfenicol. The detection limit were 10μg/kg for Thiamphenicol and 5μg/kg for Florfenicol. The average recoveries in spiked sample were 80.0%～95.8%.In Chapter Four: Conclusion and expectation are reviewed.