分散固相萃取/液相色谱串联质谱法测定鸡肉中二硝托胺及其代谢产物残留量

Simultaneous Determination of Zoalene and Its Metabolite in Chicken Muscle by Dispersive Solid Phase Extraction and Liquid Chromatography-Tandem Mass Spectrometry

建立了同时测定鸡肉中二硝托胺及其代谢产物3-氨基-5-硝基邻甲苯酰胺(3-ANOT)的分散固相萃取/液相色谱串联质谱(LC-MS/MS)分析方法。样品用乙腈提取,离心后吸取2 mL上清液,进行分散固相萃取净化,净化液以1∶4的比例用0.1%甲酸溶液混合稀释,混匀后过滤膜即可进行LC-MS/MS分析。采用Acquity BEH C18色谱柱,以0.1%甲酸溶液和乙腈为流动相进行梯度洗脱;电喷雾正负离子切换多反应监测模式检测,外标法定量。二硝托胺和3-ANOT的峰面积与其质量浓度均在1～500μg.L-1范围内呈良好线性,线性系数分别为0.999 5和0.999 4。在50～4 500μg.kg-1加标范围内,二硝托胺和ANOT的加标回收率为81%～94%,批内相对标准偏差(RSD)为2.1%～5.3%,批间RSD为4.3%～6.2%。二硝托胺和3-ANOT的检出限分别为10、14μg.kg-1,定量下限均为50μg.kg-1。该方法能满足鸡肉中二硝托胺及其代谢产物残留分析的要求。

A method was developed for the determination of zoalene and its metabolite（3-amino-5-nitro-o-toluamide, 3-ANOT） in chicken muscle by dispersive solid phase extraction and liquid chromatography tandem mass spectrometry （LC - MS/MS）. The samples were extracted with acetonitrile and purified by dispersive solid phase extraction method. After diluted with 0. 1% formic acid, the extract was filtered through 0. 22 μm filter and 10 μL of the filtrate was injected into LC for analysis. The target compounds were separated on an Acquity BEH C18 column with acetonitrile-0. 1% formic acid as mobile phase with gradient elution, and detected by MS under multiple reaction monitoring （MRM） with positive and negative ionization switching mode. The analytes were quantified by the external standard. Good linearities were obtained for zoalene and 3-ANOT at the concentration of 1 - 500 μg · L^-1, with correlation coefficients of 0. 999 5 and 0. 999 4, respectively. The recoveries of zoalene and 3-ANOT in chicken muscle at fortified levels of 50 -4 500 μg · L^- were between 81% and 94%. The intra-assay RSDs were in the range of 2. 1% -5.3% and the inter-assay RSDs were 4. 3% -6.2%. The limits of detection of zoalene and 3-ANOT were 10 and 14 μg · kg^-1, respectively, and their limits of quantitation were both 50μg · kg^-1 The results indicated that the method could meet the requirement for simultaneous determination of zoalene and 3-ANOT in chicken muscle.