奶粉中双氰胺残留量的测定液相色谱-串联质谱法

Determination of Dicyandiamide Residues in Powdered Milk by LC-MS/MS

建立了一种测定奶粉中双氰胺残留量的液相色谱串联质谱检测方法。样品用纯水溶解,乙腈涡旋提取,双氰胺专用净化管净化,液相色谱串联质谱仪测定,外标法定量。结果表明,双氰胺在2. 0ng/m L～50. 0ng/m L范围内呈良好的线性关系,线性相关系数为0. 9994;在50. 0μg/kg、10. 0μg/kg、200. 0μg/kg三个浓度水平的添加回收率范围为81. 1%～88. 3%,相对标准偏差RSD(n=6)为1. 84%～3. 17%,方法定量限为50. 0μg/kg。

A method was developed for the determination of dicyandiamide residues in powdered milk by liquid chromatography-tandem mass spectrometry(LC-MS/MS).Samples were dissolved in pure water,extracted by acetonitrile and purified by a special purification tube for dicyandiamide,and then determined by liquid chromatography-tandem mass spectrometry(LC-MS/MS)and quantified by external standard method.The results showed that dicyandiamide had a good linear relationship in the range of 2.0 ng/mL to 50.0 ng/mL,the linear correlation coefficient was 0.9994,the recovery ranged from 81.1% to 88.3% at the levels of 50.0 μg/kg,100.0 μg/kg and 200.0 μg/kg,and the relative standard deviation RSD of precision was 1.84%~3.17%(n=6).The quantitative limit of the method was 50.0 μg/kg.