Sr-87/Sr-86 isotope ratios in rocks determined using inductively coupled plasma tandem mass spectrometry in O-2 mode without prior Sr purification
Sr-87/Sr-86 isotope ratios in rocks determined using inductively coupled plasma tandem mass spectrometry in O-2 mode without prior Sr purification
复制标题
使用电感耦合等离子体串联质谱法在 O-2 模式下测定岩石中的 Sr-87/Sr-86 同位素比率，无需事先进行 Sr 纯化
DOI：
10.1002/rcm.8690
复制
发表时间：
2020
影响因子：
2
通讯作者：
Yang Yibo
中科院分区：
文献类型：
--
作者：
Liu Xiaoming;Dong Shuofei;Yue Yahu;Guan Qiuyun;Sun Yali;Chen Shengsheng;Zhang Jiuyuan;Yang Yibo
采用电感耦合等离子体串联质谱（ICP-MS/MS）技术，无需锶净化，在“质量漂移”模式下，可测定87 Sr/86 Sr比值，外部精密度优于0.05%相对标准偏差（RSD）。以前的研究建议使用CH 3F，N2 O，和SF6作为反应气体的这种方法，因为更好的反应速率可以实现与Sr+比与O2在反应池中。然而，这些气体在一般化学实验室中并不常用，并且由于法规的原因，使用这些气体的工艺难以快速实施。本研究旨在建立一种快速、准确测定87 Sr/86 Sr同位素比值的方法，其相对标准偏差小于0.1方法我们评估了经认证的参考物质和不同岩石类型中87 Sr/86 Sr比值的准确度和精密度，以O2为反应气体的MS与使用多收集器电感耦合等离子体质谱法测定的结果进行比较结果本研究表明，通过使用ICP-MS/MS方法，BCR-2和BHVO-2的87 Sr/86 Sr比值在有无Sr纯化前没有显著变化;当测量溶液的Sr浓度在60-350 ng/mL范围内时，对测量的87 Sr/86 Sr比值没有显著影响。结论ICP-MS/MS测定23种不同岩石样品的87 Sr/86 Sr比值的精密度在0.0001 ~ 0.0019（2SD）之间。这种精确度低于MC-ICP-MS方法，但足以用于某些应用，例如确定不同岩石类型中的87 Sr/86 Sr比值。这些结果表明，开发的ICP-MS/MS方法有可能用于未来的研究，涉及到锶源的识别。
RationaleAn inductively coupled plasma tandem mass spectrometry (ICP‐MS/MS) instrument can be developed to determine87Sr/86Sr ratios with an external precision better than 0.05% relative standard deviation (RSD) in “mass shift” mode without prior Sr purification. Previous studies suggested using CH3F, N2O, and SF6as reaction gases for this method because a better reaction rate can be achieved with Sr+than with O2in the reaction cell. However, these gases are not commonly used in general chemistry laboratories, and processes using these gases are difficult to implement quickly due to regulations. We aim to develop a rapid method that can be applied to many samples for the accurate determination of87Sr/86Sr isotope ratios with precision below 0.1% RSD (or approximately to the fourth decimal place).MethodsWe evaluated the accuracy and precision of87Sr/86Sr ratios in certified reference materials and different rock types determined using ICP‐MS/MS with O2as the reaction gas in comparison with those determined using the multicollector inductively coupled plasma mass spectrometry (MC‐ICP‐MS) method.ResultsThis study showed that by using the ICP‐MS/MS method, the87Sr/86Sr ratios of BCR‐2 and BHVO‐2 do not vary significantly with and without prior Sr purification; when the Sr concentration of the measured solution is within the range of 60–350 ng/mL, there is no significant effect on the measured87Sr/86Sr ratios. The results also showed that the87Sr/86Sr ratios of 23 different rock types measured by ICP‐MS/MS and MC‐ICP‐MS methods agree very well.ConclusionsThe precision of the87Sr/86Sr ratio measured using ICP‐MS/MS varies between 0.0001 and 0.0019 (2SD). This precision is less than that of the MC‐ICP‐MS method but is sufficient for certain applications, such as identifying87Sr/86Sr ratios in different rock types. These results suggest that the developed ICP‐MS/MS method has the potential for future studies involving the identification of Sr sources.