液相色谱-串联质谱法测定水产品中喹乙醇和卡巴氧的代谢物残留量

Determination of olaquindox and carbadox metabolite residues in aquatic products by liquid chromatography-tandem mass spectrometry

中文关键词:  喹乙醇  卡巴氧  3-甲基-喹噁啉-2-羧酸  喹噁啉-2-羧酸  代谢物  水产品  液相色谱-串联质谱法

英文关键词:olaquindox  carbadox  3-methyl-quinoxaline-2-carboxylic acid  quinoxaline-2-carboxylic acid  metabolite  aquatic products  liquid chromatography-tandem mass spectrometry

中文摘要:

      目的 建立液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS)测定水产品中喹乙醇代谢物3-甲基-喹噁啉-2-羧酸(3-methyl-quinoxaline-2-carboxylic acid, MQCA)和卡巴氧代谢物喹噁啉-2-羧酸(quinoxaline-carboxylic acid, QCA)的残留量的分析方法。方法 样品在0.2 mol/L Tris/HCL缓冲溶液作用下, 47 ℃水浴振荡进行酶解, 将与组织以结合态形式存在的MQCA和QCA转变为游离态, 酶解液经盐酸酸化, 乙酸乙酯提取, 提取液吹干后加入20%甲醇水溶解, 过PAX固相萃取柱净化, 浓缩定容, 采用ACQUITY UPLC HSS T3色谱柱分离, 以乙腈、0.1%甲酸溶液为流动相, 多反应离子监测(multiplereaction reaction monitoring, MRM)模式测定, 内标法定量。结果 MQCA和QCA在2.5~100 ng/mL范围内呈良好的线性关系, 相关系数(r2)均大于0.99。在0.5、2.5和10 μg/kg加标水平下(n=6), MQCA和QCA的平均回收率为75.6%~92.4%, 相对标准偏差为3.81%~9.73%。MQCA和QCA的检出限均为0.25 μg/kg, 定量限均为0.5 μg/kg。结论 该方法灵敏、准确, 重复性好, 适用于水产品中MQCA和QCA残留量的同时测定。

英文摘要:

      Objective To establish a method for the determination of 3-methyl-quinoxaline-2-carboxylic acid (MQCA) and quinoxaline-2-carboxylic acid (QCA) residues in aquatic products, which were metabolites of carbadox and olaquindox, respectively, by liquid chromatography–tandem mass spectrometry (LC-MS/MS). Methods The samples were hydrolyzed by a 0.2 mol/L Tris/HCL buffer solution at 47 ℃ in water, and the MQCA and QCA, which were existed in the form of binding state with tissue, were transformed into a free state. The enzymolysis liquid of sample was acidized by hydrochloric acid and extracted by ethyl acetate. The extraction solution was dissolved with 20% methanol water after blowing dry, purified by PAX solid phase extraction column, and concentrated to a definite volume. The analysis was carried out on analytical column ACQUITY UPLC HSS T3 with the mobile phase comsisted of acetonitrile and 0.1% formic acid solution. The samples were detected by multiplereaction reaction monitoring and quantified by internal standard method. Results The calibration curves showed good linearity in the range of 2.5~100 ng/mL, and the correlation coefficient (r2) was greater than 0.99. The limit of detection (LOD) was 0.25 μg/kg, and limit of quantitation (LOQ) was 0.5 μg/kg. The recovery rates were 75.6%~92.4% for the target compounds at spiked levels of 0.5, 2.5 and 10 μg/kg. Each level repeated 6 times and the relative standard deviations (RSDs) were 3.81%~9.73%. Conclusion This method has high sensitivity, accuracy and good reproducibility and it is suitable for the simultaneous determination of MQCA and QCA residues in aquatic products.