A new double spike method for the determination of mass-dependent Te isotope compositions of meteorites and terrestrial materials by MC-ICP-MS
A new double spike method for the determination of mass-dependent Te isotope compositions of meteorites and terrestrial materials by MC-ICP-MS
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MC-ICP-MS 测定陨石和陆地物质质量依赖性 Te 同位素组成的新双尖峰方法
DOI：
10.1039/d3ja00091e
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发表时间：
2023
影响因子：
3.4
通讯作者：
Morton E
中科院分区：
文献类型：
--
作者：
Morton E
本研究提供了一种测定碲同位素组成的新方法。该工艺包括一种新的柱色谱程序，该程序以高产率和高纯度将Te从铁陨石和铁陨石以及各种陆地岩石中分离出来，并结合了强大的125 Te-128 Te双尖峰和优化的多收集器ICP-MS协议。这使得精确（2SD = 0.07‰）的质量依赖的130 Te/125 Te同位素比使用分析物溶液含有低至6 ng的天然Te的测定。该方法的有效性证明了重复分析的陆地岩石参考材料和陨石，这表明与以前的工作总体良好的协议。此外，三个不同的Te标准溶液的实验室间交叉校准进行。这种实验室间的交叉校准是非常有利的，因为尚未获得用于Te的良好校准的同位素参考材料。在这项研究中进行的同位素质量平衡和混合方程表明，假设的质量独立的Te同位素效应的合理幅度是不太可能有显着影响的测量质量依赖的Te同位素组成在当前水平的分析精度。最后，本研究提出了第一个精确的质量依赖Te同位素组成的铁陨石，峡谷暗黑破坏神，和科马提岩参考材料KAL-1使用双穗技术。
This study presents a new method for the determination of mass-dependent Te isotope compositions. The process encompasses a new column chromatographic procedure which separates Te from chondritic and iron meteorites and diverse terrestrial rocks with high yield and purity, combined with a robust 125Te–128Te double spike and optimised multi collector ICP-MS protocols. This allows for precise (2SD = 0.07‰) determination of the mass-dependent 130Te/125Te isotope ratio using analyte solutions containing as little as 6 ng of natural Te. The efficacy of the method is demonstrated by repeat analyses of terrestrial rock reference materials and meteorites, which show overall good agreement with previous work. In addition, an inter-laboratory cross-calibration of three different Te standard solutions was performed. This inter-laboratory cross-calibration is highly advantageous, as a well-calibrated isotope reference material is not yet available for Te. Isotope mass balance and mixing equations performed in this study show that hypothetical mass-independent Te isotope effects of reasonable magnitude are unlikely to have a significant impact on the measured mass-dependent Te isotope compositions at the current level of analytical precision. Finally, this study presents the first precise mass-dependent Te isotope composition obtained for an iron meteorite, Canyon Diablo, and komatiite reference material KAL-1 using the double spike technique.