亲水作用色谱串联质谱法测定乳及乳制品中三聚氰胺

Determination of melamine in milk and dairy products by hydrophilic interaction chromatography-tandem mass spectrometry

目的建立了亲水作用色谱串联质谱法检测乳及乳制品中三聚氰胺(melamine)的分析方法。方法样品(奶酪、奶油、巧克力、奶糖需先经海砂研磨成干粉状)经质量分数为2%乙酸水溶液溶解提取、乙腈沉淀蛋白,以乙腈和5 mmol/L乙酸铵作为流动相,经Poroshell 120 HILIC色谱柱分离后采用多反应监测方式扫描,内标法定量。结果在0.2~20μg/L范围内线性关系良好(R^2≥0.99),定量限为0.005 mg/kg。按定量限1,2和5倍这3个加标水平的平均回收率为94.2%~104.9%,相对标准偏差(RSD)介于1.25~5.47之间。结论方法操作简便,快速,无需固相萃取柱净化,结果准确、灵敏,可为三聚氰胺检测的例行抽检、研究和质控提供技术支持。

Objective A method was developed for the determination of melamine in milk and dairy products using hydrophilic interaction chromatography-tandem mass spectrometry(HPLC-MS/MS).Methods The samples were extracted with 2%acetic acid solution and the protein was precipitated with acetonitrile subsequently.The separation of melamine was carried out on a Poroshell 120 HILIC columu using acetonitrile and ammonium acetate as mobile phases.Results A good linear relationship was obtained between the peak area and concentration of melamine in the range of 0.2-20μg/mL with the correlation coefficient more than 0.99.The limit of quantification of melamine was 0.005 mg/kg.The spiked recoveries were 94.2%-104.9%.The precisions(RSDs)were 1.25-5.47.Condusion The developed method is simple and convenient in determination of melamine in milk and dairy products.