摘要
采用同位素内标物减少样品基质对检测造成的干扰，用液相色谱串联质谱法测定乳及乳制品中三聚氰胺的含量。样品用乙腈超声提取，高速离心，经阳离子交换固相萃取柱净化后，利用Agilent Rx-sil色谱柱进行分离，以乙腈一水（体积比为95：5，含5mmol／L乙酸铵溶液）作为流动相，ESI正离子模式下检测，内标法定量。三聚氰胺质量浓度在1-100ng／mL的范围内与色谱峰面积呈良好的线性关系，相关系数r=0．9998，检出限为1．0gg／kg。在两个添加水平下，样品的加标回收率为99．4％-99．8％，相对标准偏差不大于1％（n=6）。改进后的方法灵敏度高、定量准确，可用于乳及乳制品的定量定性检验。
Isotope internal standard was used to eliminate the interference caused by the sample matrix on the de- tection and the accurate determination of the content of melamine in milk and dairy products by liquid chromatography- tandem mass spectrometry was developed. Bing extracted with acetonitrile ultrasound after high-speed centrifugation and extraction with cation exchange solid phase column and separated by Agilent Rx-Sil column acetonitrile-water （ 95 ： 5, containing 5 mmol / L ammonium acetate ） as the mobile phase, the samples were determined by the internal standard method under ESI positive ion mode. Concentration of the melamine had good linear relationship with peak area in the range of 1-100 ng/mL, the correlation coefficient was 0.999 6, and the detection limit was 1.0 ng/mL. The recoveries under two spiked levels were 99.5%-99.9%, and the relative standard deviation was not more than 1% （ n=6 ）. The improved method is highly sensitive and quantitative, it is suitable for quantitative and qualitative examination of melamine in milk and dairy products.
出处
《化学分析计量》
CAS
2013年第4期49-52,共4页
Chemical Analysis And Meterage
关键词
液相色谱
串联质谱
内标法
乳
乳制品
三聚氰胺
liquid chromatography
tandem mass spectrometry
internal standard method
milk
dairy products
melamine
