Determination Of Residues Of Sulfonamides And Tetracyclines In Milk By Multi-walled Carbon Nanotubes SPE-HPLC-MS

Tetracycline antibiotics and sulfa antibiotics has been widely used in the prevention and treatment of food-borne animal diseases, but excessive use of these antibiotics will result in food-borne residues in animal products, may not only pollute the environment, serious Also likely to affect human health, therefore, the establishment of a quick and easy way to detect animal-derived food in the tetracycline class antibiotics and sulfa antibiotic residues in many ways is very necessary. This study used multi-walled carbon nanotubes as a new type of solid-phase extraction adsorbent to make a solid phase extraction columns, a solid-phase extraction of offline pre-treatment methods on milk samples before processing and use of high-performance liquid color Spectrum-using mass spectrometry technology and high-performance liquid chromatography as a test of milk in the antibiotics tetracycline and sulfonamides residues in the analysis, and application of the method established by the Chengdu Commercial Several milk samples Were detected.In this paper, a solid-phase extraction-liquid/mass spectrometry detection method which multi-walled carbon nanotubes was used as a solid-phase extraction adsorbent to detect tetracycline antibiotics and sulfa antibiotic residues in milk. Agilent TC C18 column chromatography was used to detection tetracycline antibiotics in milk, A:methanol:acetonitrile=1:3(V/V), B:0.01mol/L oxalic acid solution. A:B=4:6 (V/V) as flow phase; flow rate was 0.7 mL/min; sulfa antibiotics detected by Dalian Gbadolite YWG C18 column for chromatography, flow phase:0.1% formic acid solution: 0.1% formic acid solution of acetonitrile (68:32 V/V); flow rate was 1.0 mL/min. The linear range of two kind of antibiotics under test were 0.1-2.0μg/mL and 0.05-1.0μg/mL. In this paper, liquid-liquid extraction and solid-phase extraction were used as a sample pre-treatment methods, the milk samples, nano-purchased from Shenzhen Co., Ltd. of Hong Kong without a concentrated nitric acid oxidation of the multi-walled carbon nanotubes ( Carbon Nanotubes 1) were used for solid-phase extraction in the detection of tetracycline antibiotics in milk samples, In sulfa antibiotics testing, multi-walled carbon nanotubes before and after the concentrated nitric acid oxidation were used as a solid-phase extraction absorbent sample pre-treatment.The milk samples sulfa antibiotics testing, were used carbon nanotubes 1 (without the oxidation process) and carbon nanotubes 2 (after the oxidation process) on the sample extraction purification, recoveries were 70.1%-109.8% and 83.3% -110.0%, after the finalization of the use of multi-walled carbon nanotubes with a solid-phase extraction absorbent sample pre-treatment. The method detection limit of 0.3μg/L-0.9μg/L, the precision of the method was 4.38%-10.13%, and the sulfa antibiotic residues in milk samples were detected with a method of high-performance liquid chromatography and MS and the best operating conditions was discussed. The detection limits was well below the EU maximum residue requirements.For determination of tetracycline antibiotics in milk, the recovery of the method established in this paper which multi-walled carbon nanotubes was used as a solid-phase extraction absorbent was 94.4%-101.2% and the detection limit was 0.05 mg/L, he precision of the method was 1.9%-5.0%, and high-performance liquid chromatography was used to detect the tetracycline antibiotic residues in milk samples, a high-performance liquid chromatography of the best operating conditions was discussed.The detection of tetracycline and sulfa antibiotics in several milk samples sold in Chengdu was determined by the method of multi-walled carbon nanotubes SPE-LC/MS which was established in this research.