评估嵌入树脂对碳酸盐稳定和凝聚同位素分析的影响
Jingjing Guo1, Xiulan Zong1,2, Niels J de Winter3,4
1Department of Earth Sciences, Faculty of Geoscience, Utrecht University, Utrecht, The Netherlands.
Rapid communications in mass spectrometry : RCM
|August 14, 2023
概括
在碳酸盐样品制备中使用的嵌入树脂增加了聚合同位素 (Δ47) 分析中的变异性. 研究人员建议净化样品或避免树脂以确保准确的结果.
科学领域:
- 地质化学 地质化学
- 同位素地球化学 同位素地球化学
- 分析化学 分析化学
背景情况:
- 嵌入树脂对于准备碳酸盐进行高精度和高分辨率采样至关重要.
- 这些树脂很难去除,可能会影响稳定同位素分析的准确性.
- 嵌入树脂对凝聚同位素分析的影响,这是一个对污染敏感的方法,以前没有研究过.
研究的目的:
- 实验评估嵌入树脂对碳酸凝聚同位素 (Δ47) 分析的影响.
- 为了确定树脂添加是否会影响同位素测量的准确性和可重复性.
- 评估对稳定 (δ13C, δ18O) 和凝聚同位素组成的影响.
主要方法:
- 分析了纯碳酸标准 (ETH-4) 的稳定和凝聚的同位素组成.
- 混合ETH-4与三种类型的嵌入树脂在 2:1 和 1:1 的比例.
- 纯ETH-4的同位素值与含树脂的混合物进行比较.
主要成果:
- 纯ETH-4和树脂混合物之间稳定同位素值 (δ13C,δ18O) 没有显著差异.
- 虽然由于很大的不确定性而没有统计学意义,但聚类同位素 (Δ47) 值在含树脂的样本中显示出更大的变异性.
- 在包括树脂在内的会话中,与没有树脂的会话相比,Δ47测量的外部标准偏差更高.
结论:
- 树脂添加可以导致凝聚同位素 (Δ47) 测量的变异性增加,可能掩盖真正的树脂相关偏差.
- 建议在分析前使用污染陷 (例如Porapak) 净化样品.
- 建议在样品制备过程中避免使用树脂,或者当树脂存在时仔细监测测量质量.
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