Li Lanqing, Sun Mingxing, Zhou Hui, Zhou Yun, Chen Ping, Min Hong, Shen Guoqing
Department of Environment and Resource, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Shanghai Entry-Exit Inspection and Quarantine Bureau, Shanghai 200135, China.
J Anal Methods Chem. 2015;2015:290903. doi: 10.1155/2015/290903. Epub 2015 Apr 1.
A rapid and cleanup-free ultrasound-assisted extraction method is proposed for the simultaneous extraction of oxytetracycline, tetracycline, chlortetracycline, and doxycycline in manure. The analytes were determined using high-performance liquid chromatography with ultraviolet detector. The influence of several variables on the efficiency of the extraction procedure was investigated by single-factor experiments. The temperature, pH, and amount of extraction solution were selected for optimization experiment using response surface methodology. The calibration curves showed good linearity (R (2) > 0.99) for all analytes in the range of 0.1-20 μg/mL. The four antibiotics were successfully extracted from manure with recoveries ranging from 81.89 to 92.42% and good reproducibility (RSD, <4.06%) under optimal conditions, which include 50 mL of McIlvaine buffer extraction solution (pH 7.15) mixed with 1 g of manure sample, extraction temperature of 40°C, extraction time of 10 min, and three extraction cycles. Method quantification limits of 1.75-2.32 mg/kg were obtained for the studied compounds. The proposed procedure demonstrated clear reductions in extraction time and elimination of cleanup steps. Finally, the applicability to tetracyclines antibiotics determination in real samples was evaluated through the successful determination of four target analytes in swine, cow manure, and mixture of animal manure with inorganic fertilizer.
本文提出了一种快速且无需净化的超声辅助萃取方法，用于同时萃取粪便中的土霉素、四环素、金霉素和强力霉素。采用高效液相色谱-紫外检测器对分析物进行测定。通过单因素实验研究了几个变量对萃取过程效率的影响。利用响应面法选择温度、pH值和萃取溶液用量进行优化实验。校准曲线表明，所有分析物在0.1-20μg/mL范围内具有良好的线性关系（R(2)>0.99）。在最佳条件下，即50mL麦氏缓冲萃取溶液（pH 7.15）与1g粪便样品混合，萃取温度40°C，萃取时间10min，萃取三个循环，四种抗生素从粪便中成功萃取，回收率在81.89%至92.42%之间，重现性良好（RSD，<4.06%）。所研究化合物的方法定量限为1.75-2.32mg/kg。该方法显著缩短了萃取时间，无需净化步骤。最后，通过成功测定猪粪、牛粪以及动物粪便与无机肥料混合物中的四种目标分析物，评估了该方法在实际样品中四环素类抗生素测定的适用性。
