应用ICP-MS测定国际比对果汁样品中铅、镉和锡的含量

Determination of Lead,Cadmium and Tin in International Proficiency Test Sample Fruit Juice by ICP-MS

建立了微波消解、电感耦合等离子体质谱法(ICP-MS)同时测定国际比对果汁样品中铅、镉和锡的方法。应用微波消解进行样品前处理,采用在线内标校正基体干扰,采用干扰方程抑制质谱干扰,使用工作曲线计算出样品中铅、镉和锡元素的含量。测定结果表明,铅、镉和锡元素的检出限分别为0.021、0.016和0.052μg/L,相对标准偏差(RSD<5%),加标回收率介于90%～105%,用该方法测定FAPAS国际比对果汁样品,反馈的统计结果显示铅、镉和锡元素的Z值分别为-0.4、0.1和-0.2,结果均为满意。该方法快速、简单、精确,适于果汁中铅、镉和锡的测定。

A plasma-mass spectrometry （ICP-MS） method with microwave digestion for the determination of Lead, Cadmium and Tin in international proficiency test sample of fruit juice was established. The sample was pretreated by microwave digestion. Online internal calibration was applied for correcting matrix interference and interference equation for controling MS interference. The contents of Lead, Cadmium and Tin in the fruit juice were calculated by the Standard curve. The detection limits of the Lead, Cadmium and Tin was 0.021,0.016 and 0.052 ~tg/L. The RSD was 〈5%.The re- coveries of the spiked samples were 90%-105%.The method was applied in the FAPAS test for fi＇uit juice. The feedback statistics showed that Z-score of the Lead, Cadmium and Tin was -0.4,0.1 and -0.2,and the result was satisfied. It indicated that the method is rapid, simple and accurate for determining Lead,Cadmium and Tin of fruit juice.