Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China; Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, China Agricultural University, Beijing 100193, China.
Food Chem. 2018 May 15;248:166-172. doi: 10.1016/j.foodchem.2017.12.029. Epub 2017 Dec 9.
A confirmatory method for the determination of colistin in animal tissues, egg, milk, and feed was developed and validated. Colistin A and colistin B were extracted from samples with the mixture of 10% trichloroacetic acid-acetonitrile and isolated with mixed-mode weak cation exchange cartridge. Analytes were separated from matrix components using ultra-high performance liquid chromatography, and detected with electrospray ionization on a triple quadrupole mass spectrometer. Mean recoveries ranged from 78.0% to 115.6% with intra-day and inter-day relative standard deviation lower than 8.4% and 12.4%, respectively. The quantitation limits for different matrices were between 5 and 30 μg/kg, which was satisfactory for surveillance monitoring. The developed method was applied to the analysis of real samples collected from different provinces of China, and 19 out of 348 samples were found to be contaminated, with the highest concentration of approximately 12,000 μg/kg colistin A and 10,000 μg/kg colistin B in feed.
建立并验证了一种用于动物组织、蛋、奶和饲料中黏菌素测定的确证方法。采用 10%三氯乙酸-乙腈混合液从样品中提取黏菌素 A 和黏菌素 B，并用混合模式弱阳离子交换柱进行分离。采用超高效液相色谱法将分析物与基质成分分离，用电喷雾电离在三重四极杆质谱仪上进行检测。该方法的日内和日间相对标准偏差均低于 8.4%和 12.4%，回收率在 78.0%至 115.6%之间。不同基质的定量限在 5 至 30μg/kg 之间，满足监测需要。该方法已应用于中国不同省份采集的实际样品分析，发现 348 个样品中有 19 个受到污染，其中饲料中黏菌素 A 和黏菌素 B 的最高浓度约为 12000μg/kg 和 10000μg/kg。
