UPLC-MS/MS法测定肠衣中四种硝基呋喃类代谢物残留量

Determination of Metabolites of Nitrofurans Residues in Casing by Ultra Performance Liquid Chromatography-Electrospray Tandem Mass Spectrometry

关键词:  超高效液相色谱-串联质谱法  硝基呋喃类代谢物  残留  肠衣

Key words:  UPLC-MS /MS  metabolites of nitrofurans  residues  casing

摘要:

采用超高效液相色谱-串联四极杆质谱，电喷雾电离(正离子模式)，对肠衣中四种硝基呋喃类代谢物残留量进行定性定量。试样用甲醇、水脱脂去除部分杂质后，经Oasis HLB固相萃取小柱富集净化后，经Waters ACQUITY UPLCTM BEH C18色谱柱分离，以0.3%乙酸乙腈溶液和和0.3%乙酸水溶液为流动相，梯度洗脱。在多反应监测模式下以保留时间和离子对(母离子和两个子离子)信息比较进行定性，以响应值高的子离子进行定量。该法的检出限为0.2～0.5μg / kg，加标回收率为86%～97%，相对标准偏差小于10%。

Abstract:

A comprehensive analytical method based on ultra performance liquid chromatography - electrospray ionization mass spectrometry (UPLC-MS /MS) with positive mode has been developed for the determination of metabolites of nitrofurans residues in casing. The multi-reaction monitoring mode was employed for the determination. Casing samples were defatted and preliminary purified with methanole and water, and then hydrolyzed with hydrochloric acid and derived with 2-NBA at 37℃ for 16 hours. Sample solutions was concentrated and purified by Oasis HLB solid phase extraction cartridges. The separation was performed on a Waters ACQUITY UPLCTM BEH C18（1.7μm,2.1 mm×50 mm）column with gradient elution using 0.3% acetic acid acetonitrile and 0.3% acetic acid water at a flow rate of 0.4mL/min. Identification of metabolites of nitrofurans was done using the retention times and the distribution of diagnostic ion pairs; the precursor/product ion transitions were monitored. Quantification of the metabolites of nitrofurans by the peak areas of higher signal precursor/product ion .The limits of detection (LOD) of the method was 0.2～0.5μg/kg .The recoveries were between 86%～97%. The relative standard deviations were below 10%.