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Aminoglycoside antibiotics are a class contains two or more amino sugar moiety of an aggregate formed by glycosidic amino cyclitol key on a class of antibiotics collectively. Since the cyclitol the different divided into a plurality of categories, which is more important is the cyclitol streptavidin guanidine streptomycin and dihydrostreptomycin, cyclitol deoxystreptamine gentamicin kanamycin and neomycin. Aminoglycosides by blocking the synthesis of the bacterial ribosome, to achieve the destruction of the bacterial cell membrane synthesis and sterilization purposes, has been widely used for disease prevention and control in the production process of food of animal origin, drug residues resulting bring a series of food safety issues, has aroused widespread concern. In order to ensure food safety, the protection of people's health, the level of laboratory testing of veterinary drug residues in increasingly high demand, so it is especially important to accurately detect drug residues. Microbiological method, immunoassay instrument analysis of aminoglycoside veterinary drug residue detection method, more applications of liquid chromatography in the analysis of the instrument. Existing method can detect the sample matrix multi bee and pork, few other matrix sample research; mostly only detect samples one or several aminoglycosides residual lack of aminoglycoside complex matrix conditions the residue effective detection method; complex detection step, the detection efficiency is low, it is difficult to play a role in the practical application. Against background interference and detection capabilities, sensitive, accurate, information-rich detection LC-MS/MS method has the advantages of the most effective ingredients confirmatory residue. LC-MS/MS method, the detection method aminoglycoside residues in aquatic products, the following research: 1. Aquatic samples obtained the aminoglycoside drugs optimum extraction conditions in aquatic the Sample Extraction investigated perchloric acid, trichloroacetic acid, sodium tungstate, and different extraction effect of the protein precipitating agent; simultaneously compare different concentrations of trichloroacetic acid extraction efficiency, and found that the best 5% trichloroacetic acid extraction effect; choice of extraction methods, the main effects of sonication and mechanical the tissue extract mentioning edge real scratch Postscript Lian? 2. extract the best purification conditions compare different solid phase extraction column (Sep-Pak C 18 , HR-xSPE, Oasis MCX and Oasis SCX etc.) purifying effect by adding heptafluorobutyric acid as ion-pairing reagent, change the extract solution pH 10 aminoglycosides in solid-phase extraction the retained conditions of the column, in order to achieve the target and the separation of impurities. The purification conditions: the HR-xSPE column, activation heptafluorobutyric acid was added to adjust mention After the solution pH to 4 ~ 5, the elution solvent was methanol and ammonia methanol. Obtained aminoglycoside detection conditions to test a different column chromatographic parameters and mass parameters of the mobile phase composition and column temperature, detection conditions: of acetonitrile -100 mmol / L heptafluorobutyric acid (80: 20, v / v /) as the mobile phase gradient elution, flow rate: 0.2 mL / min, injection volume: 10μL, analyte positive electrospray ionization conditions, using multiple reaction monitoring mode using the external standard method . 4. Established aquatic aminoglycoside drug residue detection methods to establish a standard curve and linear range, limit of detection, recovery and precision methodology parameters. The linear range of the standard curve: 50ng/mL ~ 1000ng/mL, the 10 aminoglycoside detection limit of of 20ng / g ~~ 50 ng / g. Add to the 50, 100 and 200 ng / g concentration level of 10 drugs in fish muscle tissue recoveries of 66.5% ~~ 108.0%, RSD 2.40% to 18.8%; Add recoveries of 10 drugs in shrimp tissue to 74.9% ~ 99.1%, RSD 3.1% to 12.4%. Detect 10 kinds of aminoglycoside drugs, days of repeated experiments RSD 1.2% to 8.4% the daytime experiment was repeated with RSD of 2.6% to 8.7%. Comparison with existing aminoglycoside veterinary drug residue detection methods, this paper established liquid chromatography - mass associated with the analytical methods accurate qualitative and quantitative characteristics of the strong anti-interference, can simultaneously detect 10 kinds of aminoglycoside veterinary drugs, the sensitivity of the method to meet the international the aminoglycoside drugs maximum residue limit requirements, suitable for quantitative and confirmatory analysis of veterinary drug residues in aquatic products aminoglycoside.
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