微波消解-碰撞池-电感耦合等离子体质谱(ICP-MS)法测定芝麻中痕量的锗

建立了微波消解-碰撞池-电感耦合等离子体质谱法测定芝麻中痕量锗元素的测定方法。在线引入内标元素铑(Rh),同时消解液中加入正戊醇(3%)作为增敏剂。结果显示,正戊醇(3%)可使⁷⁴Ge的上机检测信号强度提高2.85倍,⁷⁴Ge校正曲线线性相关系数为1.000,检出限为0.056μg/kg,加标回收率为92.0%~106%,相对标准偏差(RSD)为2.6%~4.3%。采用建立的方法测定7种国家标准物质,检测结果均在认定值范围内,RSD为2.5%~8.8%。方法灵敏度高、准确,可实现批量检测,适用于芝麻中痕量锗的检测。

Determination of Trace Germanium in Sesame by Inductively Coupled Plasma-Mass Spectrometry-Collision Cell Technology with Microwave Digestion

In order to accurately and efficiently detect trace germanium(Ge)in sesame,a method of microwave digestion-collision cell-inductively coupled plasma mass spectrometry was established.The internal standard element of rhodium(Rh)was introduced online,and addition of 3%1-pentanol to the digestion solution were used to enhance the sensitivity.The results indicated:3%1-pentanol increased the signal intensity of ⁷⁴Ge by 2.85 times.The correlation coefficient of germanium correction curve was 1.000.The limit of detection of the method was 0.056μg/kg,and the spiked recovery rates ranged from 92.0%to 106%with the relative standard deviation(RSD)of 2.6%—4.3%.The certified reference material of germanium was in the range of certified value.This method has high sensitivity,high accuracy and good precision,and is suitable for the determination of germanium element content in sesame.