| The most commonly analysis of pesticide and veterinary drug residues in foodstuffs of animal origin can be divided into two steps: the sample pre-treatment and the determination of using instrument. Recently, testing equipment can meet the requirements for analyzing of pesticide and veterinary drug residues. However, the reported sample pre-treatment methods were complex, solvent-consuming,low-recovery and so on. This thesis has reviewed the literatures of sample preparation techniques. Equilibrium dialysis method with HPLC and GC-MS method were combined to investigate the binding interaction of drugs and protein, as well as drugs and real samples, further to explain the state of drugs in real sample. The studied drugs are including carbamates, clenbuterol, eugenol and praziquantel. Above all, the investigation provided a theoretical guidance for the pre-treatment technology in complex samples. CH3CN-K2HPO4-H2 O aqueous two-phase extraction method and organic solution extraction method were studied. And fast and efficient methods were established for analysis of residues in foodstuffs of animal origin.Part one: This section described the situation of security in foodstuffs of animal origin, and reviewed the detection of technologies and the sample pretreatment methods for analyzing of pesticide and veterinary drug residues.Part two: Using bovine serum albumin(BSA) as the model protein,high-performance liquid chromatography(HPLC) was applied to study the effect of protein on the extraction of four carbamate pesticides in fish and shrimp meat samples,the results showed that the strong interaction between protein and four carbamate pesticides. Based on CH3CN-K2HPO4-H2 O aqueous two-phase extraction system, a high-efficient extraction was obtained, then add PSA、C18 to eliminate the fat and other polar impurities, last analyze directly with HPLC. Under the optimal conditions, this method was applied to determination quickly of four carbamate pesticides in fish and shrimp sample with High-Performance Liquid Chromatography(HPLC), satisfactory spiked recoveries between 80.1% and 96.7% with the relative standard deviation valuesfrom 1.37% to 3.76%, the limits of detection ranging from 0.26 ng/g to 8.8 ng/g. It was verified that this method was an efficient pretreatment and could provide a basis of how to determine carbamate pesticides in complex animal origin samples.Part three: Direct using the methanol-hydrochloric acid aqueous solution as extracting solution, a rapid method was established in this experiment for the determination of clenbuterol in meat and serum by HPLC. The existence of the state of the clenbuterol in pork and porcine serum sample was investigated. The research showed that there is a strong interaction between clenbuterol and protein in pork as well as porcine serum. In the 50%(volume fraction) methanol-water extracting solution, obtained a high-efficient extraction of clenbuterol and analysed directly by HPLC. This proposed method was available to determination of clenbuterol in pork,porcine serum beef and bovine serum by high performance liquid chromatography, the clenbuterol had good linear response within the range of 0.01~5.00 μg/m L. Overall limits of detection were 1.8ng/g, Relative standard deviation values were at2.1%~5.1%, and recoveries were 87.4%~99.2%.Part four:Based on CH3CN-K2HPO4-H2 O aquatic two phase system, a fast and high-effecient sample pretreatment method was developed for analyzing eugenol in fish and shrimp sample by Gas Chromatography- Mass Spectroscopy(GC–MS). Using equilibrium dialysis method and GC–MS were applied to study the binding interaction between eugenol and protein. Meanwhile, the effects of protein matrix on the extraction of eugenol from fish and shrimp meat were detailedly researched. The research indicated that there is a strong interaction between eugenol and fish as well as shrimp which were wealthy in protein. The aquatic two phase system and Qu ECh ERS method were applied to sample in same time, the aquatic two phase system obtained high-efficient extraction. This advised method was applied to analysis of eugenol in fish and shrimp samples. The detection limit was 2.2 ng/g and the spiked recoveries were 80.6%~95.9%.Part five: Fluorescence spectrometry was made use of study the interaction between drugs and protein, including the quenching, the equilibrium constants and the number of binding. The results showed that the protein has a strong interaction withpraziquantel, To improve the extraction efficiency, some extraction systems and the extraction systems concentrations were investigated. However, in the 80%(volume fraction) CH3CN-K2HPO4-H2 O aquatic two phase system, obtained a high-efficient extraction of praziquantel. Under the optimal conditions, this method was applied to the quick determination of praziquantel residues in fish and shrimp samples, the detection limit was 6.0 ng/g, satisfactory spiked recoveries between 80.4% and 91.6%with the relative standard deviation values from 2.46% to 3.42%. |
