FETV-ICP-AES直接测定中药漏芦中微量稀土元素的研究

Study on Direct Determination of Trace Rare Earth Elements in Chinese Medicine Loulu by FETV-ICP-AES with PTFE Slurry Modifier

提出了以聚四氟乙烯悬浮液为氟化剂 ,氟化电热蒸发 (FETV)等离子体发射光谱法 (ICP- AES)直接测定中药漏芦中微量稀土元素 La、Eu、Yb和 Y的方法。改进了 ETV与 ICP之间的气路接口 ,研究了影响待测元素信号强度的有关因素。在优化实验条件下 ,方法的检出限为 1 .0～ 3.8ng/m L,相对标准偏差为 2 .7%～ 4.4%。此法已应用于中药漏芦中微量稀土元素的测定。

A method was described for direct determination of trace rare earth elements (La,Eu,Yb and Y) in Chinese medicine Loulu by fluorination assisted electrothermal vaporization inductively coupled plasma atomic emission spectrometry(FETV ICP AES) with slurry sampling. A polytetrafluorethylene(PTFE) emulsion was used as a fluorinating reagent to promote the vaporization of the analytes in graphite furnace. The main factors affecting the analytical signals were studied. The detection limits for the determination of La,Eu Yb and Y are 3.8,2.3, 1.0 and 1.2 ng/mL,respectively; the relative standard deviations are less then 4.4% ( n =11); the recovery are in the range of 95%～110%. The proposed method was applied to direct determination of trace rare earth elements in Chinese medicine Loulu with satisfactory results.