Precise measurement of selenium isotopes by HG-MC-ICPMS using a 76–78 double-spike,Journal of Analytical Atomic Spectrometry

当前位置： X-MOL 学术 › J. Anal. At. Spectrom. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Precise measurement of selenium isotopes by HG-MC-ICPMS using a 76–78 double-spike
Journal of Analytical Atomic Spectrometry ( IF 3.1 ) Pub Date : 2019/12/09 , DOI: 10.1039/c9ja00331b
Marie-Laure Pons _{1,

2,

3,

4,

5} , Marc-Alban Millet _{4,

6,

7,

8} , Geoff N. Nowell _{2,

4,

9,

10} , Sambuddha Misra _{1,

2,

3,

4,

11} , Helen M. Williams _{1,

2,

3,

4}

Affiliation

Selenium (Se) stable isotopes are a new geochemical tool with great potential as a tracer of redox processes and chemical cycling of chalcophiles and volatile elements. However, Se isotope measurements in low-Se samples present a formidable analytical challenge. In this study, we report a new method to measure Se stable isotopes (δ^82/78Se; per mil deviation relative to Se NIST SRM 3149) with extremely high precision. Selenium has six stable isotopes and therefore is a good candidate for isotope analysis using a double spike approach, which has the advantage that it can correct for any stable isotope fractionation that may occur during sample processing. We have calibrated a novel ⁷⁶Se–⁷⁸Se double spike and have developed a rapid and precise analytical protocol on a multi-collector inductively coupled plasma mass spectrometer using an ESI hydride generation introduction system. Sensitivity is over 1000 V per ppm for the total Se signal; a measurement typically requires 25 ng of natural Se. Argon dimer interferences on masses 76, 78 and 80 were corrected in situ by measuring mass 80. Germanium interferences on masses 74 and 76 were corrected by measuring mass 73 and mass 75 was monitored to correct for arsenic hydride on mass 76. Wash-out times were in the order of 180 s, greatly reduced compared to previous studies that rely on on peak zero argon dimer corrections (wash-out times of up to one hour). The 2 s.e. error for a single analysis typically ranges from 0.01 to 0.025‰ (n = 80) for δ^82/78Se. Long-term reproducibility and accuracy were estimated by multiple analyses of the Se Merck standard over numerous different analytical sessions, resulting in a mean δ^82/78Se value of −0.989 ± 0.034‰ (n = 93; 2 s.d.), which is in excellent agreement with previous studies.

中文翻译：

HG-MC-ICPMS使用76-78双尖峰对硒同位素进行精确测量

硒（Se）稳定同位素是一种新型的地球化学工具，具有作为氧化还原过程和亲硫族化合物和挥发性元素的化学循环的示踪剂的巨大潜力。但是，低硒样品中的硒同位素测量提出了巨大的分析挑战。在这项研究中，我们提出一个新的方法来测量硒稳定同位素（δ ^78分之82以极高的精度;每相密耳偏差为Se NIST SRM 3149 SE）。硒具有六个稳定的同位素，因此是使用双峰方法进行同位素分析的良好候选者，其优点是可以校正样品处理过程中可能发生的任何稳定同位素分馏。我们已经校准了一部新颖的⁷⁶ Se– ⁷⁸硒双峰，并已使用ESI氢化物发生引入系统在多收集器电感耦合等离子体质谱仪上开发了快速，精确的分析方案。总硒信号的灵敏度超过1000 V / ppm。测量通常需要25 ng天然硒。通过测量质量80原位校正质量76、78和80上的氩二聚体干扰。通过测量质量73校正质量74和76上的锗干扰，并监测质量75以校正质量76上的氢化砷。冲洗时间它们的时间约为180 s，与以前的依赖零峰值氩二聚体校正的研究相比，清洗时间大大缩短（冲洗时间长达一小时）。单个分析的2 se误差通常在0.01至0.025‰（n= 80），用于δ ^78分之82硒。长期再现性和精确度是由硒默克标准在许多不同的分析会话的多个分析估计，从而导致平均δ ^78分之82的-0.989±0.034‰硒值（Ñ = 93; 2 SD），这是在与以前的研究非常吻合。

更新日期：2020-02-13

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11