液相色谱-串联质谱法测定大菱鲆鱼粉中呋喃唑酮代谢物残留

Determination of furazolidone metabolite residue in the turbot fish meal by liquid chromatography-tandem mass spectrometry

目的建立液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS)检测大菱鲆鱼粉中呋喃唑酮代谢物3-氨基-2-噁唑烷基酮(3-amino-2-oxazolidinone,AOZ)残留的分析方法。方法大菱鲆冻干鱼粉样品复水后,经盐酸水解,2-硝基苯甲醛衍生化,乙酸乙酯提取,高速离心净化,采用2mmol/L乙酸铵(A)和甲醇(B)作为流动相进行梯度洗脱,质谱(electron spray ionization, ESI+)选择反应监测模式对AOZ进行定性和定量测定。结果在1.0~40μg/L范围内线性关系良好,相关系数大于0.999。AOZ在2.00、5.00、10.0和20.0μg/kg添加水平的回收率在94.2%~100%之间,批内和批间相对标准偏差均<10%。本方法冻干鱼粉中AOZ的定量限为2.00μg/kg。结论该方法灵敏、准确,操作简便,适用于大菱鲆鱼粉中AOZ残留基体标准物质的定值测定。

Objective To establish a method for the determination of furazolidone metabolite 3-amino-2-o xazolidinone(AOZ)residues in turbot fish meal by liquid chromatography-tandem mass spectrometry(LC-MS/MS).Methods After rehydration,the turbot fish meal was hydrolyzed by hydrochloric acid and derivatized by 2-nitrobenzaldehyde overnight.Then AOZ was extracted with ethyl acetate and purified by high-speed centrifugation.The AOZ residue in the extract was separated on a reversed phase using a gradient elution program of 2 mmol/L ammonium acetate(A)and methanol(B).Using LC-MS/MS(ESI+)with selected reactions monitoring,identification of the major components of the AOZ residue was performed based upon the intensities of fragments.Results The calibration curve showed a good linearity in a range of 1.0-40μg/L with the correlation coefficient over 0.999.The recoveries were ranged from 94.2%to 100%for the AOZ residues with 4 spiked levels of 2.00,5.00,10.0 and 20.0μg/kg.The relative standard deviations(RSDs)were less than 10%(n=6),and the limit of quantitation(LOQ)for the AOZ in turbot fish meal was 2.00μg/kg.Conclusion The proposed method is sensitive,accurate and easy to operate,which is suitable for detecting AOZ residues in reference material of turbot fish meal.