Isotopic measurements and speciation analysis

While isotopic analysis and speciation analysis are distinct techniques with different objectives, there can be some overlap in specific applications. For instance, isotopic analysis can sometimes be used to help identify the sources or transformations of specific chemical species within a sample.

Instrumentation used for isotopic analysis
Isotope analysis often requires specialized instruments to measure the relative abundance of isotopes in a sample. The choice of instrument depends on the specific isotope and the type of analysis you want to perform. Some of the main instruments used for isotope analysis include:

Mass Spectrometry (MS): Mass spectrometry is one of the most common techniques for isotope analysis. It separates and measures ions based on their mass-to-charge ratio. There are different types of mass spectrometers, including:

• Isotope Ratio Mass Spectrometer (IRMS): These instruments are specifically designed for measuring isotope ratios, such as stable isotope ratios in compounds like carbon, nitrogen, and oxygen.
• Inductively Coupled Plasma Mass Spectrometer (ICP-MS): ICP-MS is used for the analysis of a wide range of elements and isotopes, including radioactive isotopes and trace metals. In order to reach the precision necessary, the isotopes have to be measured simultaneously, so that the isotope ratio is not influence by any flicker noise of the plasma source. For this reason, the highest accuracy and precision is obtained by Multi-collector sector field ICP-MS instruments.
• Thermal Ionization Mass Spectrometry (TIMS) is one of the most precise methods for determining isotopic ratios and is typically applied to elements like uranium (U), thorium (Th), and some rare earth elements (e.g., samarium, neodymium).
• Secondary Ion Mass Spectrometry (SIMS): SIMS is a technique that analyses the surface of solid samples. It can be used to measure isotopic ratios in minerals, meteorites, and other solid materials.

    Alpha Spectrometry: Alpha spectrometry is used to analyse alpha-emitting radioactive isotopes. It measures the energy spectrum of alpha particles emitted by the sample.

    Beta Spectrometry: Beta spectrometry is used to measure beta particle emissions from radioactive isotopes. It quantifies the energy spectrum of beta particles.

    Gamma Spectrometry: Gamma spectrometry involves the measurement of gamma-ray emissions from radioactive isotopes. It can be used for both qualitative and quantitative analysis of gamma-emitting isotopes.

    Nuclear Magnetic Resonance Spectroscopy (NMR): NMR can be used for the analysis of certain stable isotopes, such as carbon-13 and nitrogen-15. It provides information about the local environment of these isotopes in molecules.

The choice of instrument depends on the specific isotopes you are interested in, the nature of the sample, and the precision and accuracy required for the analysis. Different isotopes and applications may require different techniques and instruments to provide reliable results.

Isotope ratio analysis provides valuable information in a variety of scientific disciplines and applications. The specific information gained from isotope ratio analysis depends on the elements and isotopes being studied, but in general, it can offer insights into several aspects of a sample or system, including:

In summary, isotope ratio analysis is a versatile tool that can provide information about the origin, history, and characteristics of substances and systems in a wide range of scientific fields and applications. The specific information gained depends on the elements and isotopes under investigation and the questions being addressed.

The following bibliography gives access to review articles discussing major areas of isotope analysis.

Metrology of Isotope Ratio Analysis Thomas Meisel, Quality Control in Isotope Ratio Applications, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 165-187. DOI: 10.1002/9783527650484.ch7

Jochen Vogl, Wolfgang Pritzkow, Reference Materials in Isotopic Analysis, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 139-163. DOI: 10.1002/9783527650484.ch6

Willi A. Brand, Tyler B. Coplen, Jochen Vogl, Martin Rosner, Thomas Prohaska, Assessment of international reference materials for isotope-ratio analysis (IUPAC Technical Report), Pure Appl. Chem., 86/3 (2014) 425-467. DOI 10.1515/pac-2013-1023

Analytical Techniques used for Isotope Ratio Analysis

Philip Dunn, Jim Carter, Good practice guide for isotope ratio mass spectrometry (IRMS), 2nd Edition, FIRMS, 2018. available from FIRMS: https://www.forensic-isotopes.org/assets/FIRMS%20Good%20Practice%20Guide%20Second%20Edition.pdf

Pelayo Alvarez Penanes, Aida Reguera Galán, Gonzalo Huelga-Suarez, J. Angel Rodríguez-Castrillón, Mariella Moldovan, J. Ignacio Garcia Alonso, Isotopic measurements using ICP-MS: a tutorial review, J. Anal. At. Spectrom., 37 (2022) 701–726. DOI: 10.1039/d2ja00018k

Frank Vanhaecke, Single-Collector Inductively Coupled Plasma Mass Spectrometry, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 31-75. DOI: 10.1002/9783527650484.ch2

Nicolas D. Greber, Kirsten van Zuilen, Multi-collector Inductively Coupled Plasma Mass Spectrometry: New Developments and Basic Concepts for High-precision Measurements of Mass-dependent Isotope Signatures, Chimia, 76 (2022) 18–25. DOI: 10.2533/chimia.2022.18

Dawei Lu, Tuoya Zhang, Xuezhi Yang, Peng Su, Qian Liu, Guibin Jiang, Recent advances in the analysis of non-traditional stable isotopes by multi-collector inductively coupled plasma mass spectrometry, J. Anal. At. Spectrom., 32 (2017) 1848–1861. DOI: 10.1039/c7ja00260b

Michael Wieser, Johannes Schwieters, and Charles Douthitt, Multi-Collector Inductively Coupled Plasma Mass Spectrometry, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 77-91. DOI: 10.1002/9783527650484.ch3

Lara Lobo, Rosario Pereiro, Beatriz Fernández, Opportunities and challenges of isotopic analysis by laser ablation ICP-MS in biological studies, Trends Anal. Chem., 105 (2018) 380-390. DOI: 10.1016/j.trac.2018.05.020

Jon D. Woodhead, Matthew S.A. Horstwood, John M. Cottle, Advances in Isotope Ratio Determination by LA–ICP–MS, ELEMENTS, 12 (2016) 317–322. DOI: 10.2113/gselements.12.5.317

Marta Costas-Rodríguez, Joris Delanghe, Frank Vanhaecke, High-precision isotopic analysis of essential mineral elements in biomedicine: natural isotope ratio variations as potential diagnostic and/or prognostic markers, Trends Anal. Chem., 76 (2016) 182–193. DOI: 10.1016/j.trac.2015.10.008
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last time modified: October 9, 2025