QuEChERS-GPC-GC/MS同时测定鱼肉中9种羟基类兽药残留

采用QuEChERS前处理方法和在线凝胶渗透色谱-气相色谱-质谱联用法（gel permeation chromatography-gas chromatography-mass spectrometry，GPC-GC/MS）快速测定鱼肉中9种羟基类兽药残留。采用在线凝胶色谱进行在线净化，除去鱼肉中大部分油脂，有效缩短了样品前处理时间，结合选择离子监测采集方式，可减少基质干扰，提高方法的选择性。样品经乙腈提取，分散基质固相萃取方式净化后，使用选择离子监测（SIM）模式检测，外标法定量。经方法学验证，9种羟基类兽药在0.5~20.0 μg/L浓度范围内的线性关系良好，相关系数r大于0.99；样品的平均回收率为63.5%~90.2%，相对标准偏差为3.6%~15.4%，方法检出限为0.3~1.0 μg/kg。将该方法应用于10批实际样品的检测，其中1批样品的氯霉素检测结果呈阳性，含量为6.1 μg/kg。该方法灵敏度高、准确可靠，可用于鱼肉中9种羟基类兽药的定性定量分析。

Determination of 9 Hydroxy Veterinary Drug Residues in Fish by QuEChERS-GPC-GC/MS

A method of QuEChERS-online gel permeation chromatography gas chromatography-mass spectrometry (QuEChERS-GPC-GC/MS) was established for 9 hydroxy veterinary drug residues in fish. GPC system was adopted for online purifying pretreatment to remove most of the fat in fish so as to effectively reduce the time of sample pretreatment. At the same time, the selective ion monitoring acquisition mode could greatly reduce the interference and provide selectivity. Extracted with acetonitrile and purified by dispersive solid phase extraction method, the analytes were detected and determined under SIM scan type with tandem mass analyzer. The analytical method was well validated, and the results were obtained at the respect of precision, repeatability and spiked recovery. The detection limits of 9 hydroxy veterinary drug residues are 0.3-1.0 μg/kg with the linear range of 0.5-20.0 μg/L. The overall recoveries are between 63.5% and 90.2% with the relative standard deviations (RSDs) of 3.6%-15.4%. Finally, the validated method was carried out in total of 10 samples to evaluate 9 hydroxy veterinary drug residues, and one sample has chloramphenicol positive, and the content is 6.1 μg/kg. This method is suitable for the determination of 9 hydroxy veterinary drugs in fish.