电感耦合等离子体质谱法测定茶叶中微量碘

Determination of Trace Iodine in Teas by Inductively Coupled- plasma Mass Spectrometry

采用微波消解-电感耦合等离子体质谱直接测定茶叶中的微量元素碘,应用硝酸和过氧化氢溶液前处理茶叶样品,通过在线内标加入法来校正由于基体效应和信号漂移对测量所造成的影响,内标选用115In。方法加标回收率在92.5%～108.3%之间,检出限为0.010μg/g,相对标准偏差(n=12)小于5.13%。实验结果表明,该方法能够满足植物样品中微量碘的分析要求。

A method for determination of trace iodine in tea samples by inductively coupled-plasma mass spectrometry was adopted after pretreating tea samples by microwave digestion with nitrate and hydrogen peroxide,correcting the matrix effects and signal drift by addition internal standard 115In.The recovery was 92.5%～108.3%;the detection limit was 0.010 μg/g;the relative standard deviation was 2.3%～3.6%.This method can meet the requirement of analyzing trace iodine in plant samples.