超高效液相色谱-电喷雾串联三重四级杆质谱法测定宠物食品中的三聚氰胺

Determination of melamine residue in pet foods using ultra performance liquid chroma-tography-electrospray ionization tandem mass spectrometry

目的：建立了利用超高效液相色谱-电喷雾串联三重四级杆质谱技术（UPLC-MS/MS）测定宠物食品中三聚氰胺（M elan ine）的方法。方法：考察了提取溶剂、提取时间、净化条件等因素对检测的影响。实验结果表明,宠物食品中三聚氰胺的相对最佳提取条件为：以三氯乙酸溶液、醋酸铅溶液混合提取同时沉淀蛋白,强阳离子固相萃取柱（MCX柱）净化。以甲醇-水为流动相洗脱,以反相C18柱作为分离柱,以电喷雾离子源为接口,正离子模式扫描,选择监测（SRM）模式检测,外标法定量。结果：三聚氰胺的检出限为25.0μg/kg,在25.0～1000.0 ng/m l浓度范围内呈良好线性,相关系数r=0.9999,回收率为74.2%～94.4%,相对标准偏差5.1%～8.1%。结论：该方法简单、快速、准确、检出限低,确证能力强,是一种高效的测定方法。

Objective：To develop a method for the determination of melamine residue in pet foods was devoloped using ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry（UPLC-MS/MS）.Methods：Several important factors including extract solvent,extract time,clean-up and concentration etc.were evaluated to acquire optimum analysis conditions.After being extracted under the selected optimum conditions,melamine residue in samples was detected by UPLC-ESI-MS/MS using electrospray ionization interface and positive ion detection mode,and selected reaction monitoring（SRM） mode,UPLC analysis was performed with a C18 column and methanol/water as mobile phase.Results：The detection limit was 25.0 μg/kg and the correlation coefficient of linear calibration curve 0.9999 within the melamine concentration range of 25.0～1000.0 ng/ml.The recovery was 74.2%～94.4% and the relative standard deviation 5.1%～8.1%.Conclusion：This method is simple,accurate and can provide a useful way for monitoring food safety.