同位素内标-超高效液相色谱串联质谱法快速测定含乳饮料中三聚氰胺残留

建立一种同位素内标-超高效液相色谱串联质谱快速测定含乳饮料中三聚氰胺残留的分析方法。样品经乙腈提取,Generik DBX固相萃取柱净化,快速离心蒸发系统浓缩,通过MN Nucleoshell Hilic色谱柱梯度洗脱,采用电喷雾离子源(ESI^+)电离,多反应监测模式(MRM)采集信号,同位素内标法定性和定量。结果表明,三聚氰胺在2~200 ng/mL浓度范围内线性关系良好(r=0.9998),方法定量限为2μg/kg;10、25、50μg/kg三个添加水平时回收率为82.37%~103.15%,相对标准偏差<6%。该方法处理简单、准确度好、灵敏度高,适合含乳饮料中三聚氰胺残留的快速检测。

Rapid determination of melamine residues in milk beverages by isotope internal standard-ultra performance liquid chromatography-tandem mass spectrometry

A method for determination of melamine residues in milk beverages by isotope internal standard-ultra performance liquid chromatography-tandem mass spectrometry was established. The melamine residues in milk beverages were extracted by acetonitrile,purified by a Generik DBX solid-phase extraction column,concentrated by a rapid solvent evaporation system,separated on a MN Nucleoshell Hilic column by gradient elution,finally determined using multiple reaction monitoring(MRM) mode by electrospray ionization source(ESI^+), qualified and quantified with isotope internal standard method. The results showed that melamine had good linearity in the concentration range of 2~200 ng/mL with the correlation coefficient 0.9998,the quantitation limits was 2 μg/kg, the recoveries were within 82.37%~103.15% at the spiked levels of 10 μg/kg,25 μg/kg and 50 μg/kg with the RSD lower than 6%. This method had simple process,good accuracy and high sensitivity,which was suitable for the determination of melamine residues in milk beverages.