Isotopic analysis and speciation analysis are distinct techniques with different objectives, yet there can be some overlap in specific applications.
Background Chemical species are defined by the International Union of Pure and Applied Chemistry (IUPAC) as “specific form of an element defined as to isotopic composition, electronic or oxidation state, and/or complex or molecular structure”. According to this definition, isotopic measurements could be discussed in the framework of speciation analysis. Yet, isotope ratio analysis is not typically considered a part of speciation analysis, although it can be related to it in certain contexts. The reason for discussing isotope measurements outside the framework of speciation analysis are manyfold:
Historical Reasons: Both areas were developed by different scientific communities mostly independently from each other.
Different analytical targets: The speciation community is interested in differentiating different elemental species because of their different chemistry, mobility, bioavailability, biological effects and toxicity.
The scientists working on isotope analysis are seldom interested in a special nuclide but on the isotopic composition of an element as a proxy for other information. Isotope ratio analysis is often used in fields like geochemistry, environmental science, and archaeology to investigate the origin, history, or authenticity of substances. It can provide valuable information about the source or processes involved in the formation of a material.
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. Fopr this reason, the highest accutacy 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 analyzes 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 analyze 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:
Origin and Source Identification: Isotope ratios can help determine the origin or source of a material. For example, in archaeology, isotope analysis can reveal the geographic origin of ancient artifacts or the source of raw materials used in their creation.
Geological and Environmental Processes: Isotope ratios are often used to investigate geological and environmental processes. For example, the analysis of stable isotopes in sediment or rocks can provide information about past climate conditions, the history of volcanic eruptions, and the movement of water in hydrological systems.
Biological and Ecological Studies: Isotope analysis is valuable in ecology and biology. It can be used to trace the movement of nutrients and elements in ecosystems, determine the diet and migration patterns of animals, and assess food web structures.
Dating and Chronology: Isotope ratios are crucial in radiometric dating techniques, such as radiocarbon dating (carbon-14), uranium-lead dating (uranium isotopes), and potassium-argon dating (potassium isotopes). These methods help determine the ages of geological and archaeological materials.
Environmental and Food Safety: Isotope analysis can be used to assess environmental contamination and the safety of food products. It can determine the presence and source of pollutants, such as heavy metals or radioactive isotopes.
Authenticity and Fraud Detection: Isotope analysis is employed in verifying the authenticity of various products, such as wines, precious gems, and artworks. By examining isotopic signatures, experts can detect fraud or counterfeiting.
Nuclear Forensics: Isotope ratios can be used in nuclear forensics to identify the origin and history of nuclear materials, which is critical for non-proliferation efforts and the investigation of illicit nuclear activities.
Chemical Reaction Pathways: In some cases, isotope ratios can provide insights into chemical reaction pathways and mechanisms. This is particularly relevant in organic chemistry and chemical kinetics studies.
Meteorology and Atmospheric Science: Isotope analysis of atmospheric gases can reveal information about the sources and cycling of atmospheric components, which is important for understanding climate change and atmospheric processes.
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
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
Takafumi Hirata, Advances in Laser Ablation–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, 93-112. DOI: 10.1002/9783527650484.ch4
Suresh K. Aggarwal, Thermal ionisation mass spectrometry (TIMS) in nuclear science and technology – a review, Anal. Methods, 8 (2016) 942–957. DOI: 10.1039/c5ay02816g
S.S. Harilal B.E. Brumfield, N.L. LaHaye, K.C. Hartig, M.C. Phillips, Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis, Appl. Phys. Rev., 5 (2018) 021301. DOI: 10.1063/1.5016053
Alexander A. Bol'shakov, Xianglei Mao, Jhanis J. González, Richard E. Russo,Laser ablation molecular isotopic spectrometry (LAMIS): current state of the art, J. Anal. At. Spectrom., 31 (2016) 119–134. DOI: 10.1039/c5ja00310e
Application area: Food authentication
Marco Cardin, Barbara Cardazzo1, Jérôme Mounier, Enrico Novelli, Monika Coton, Emmanuel Coton, Authenticity and Typicity of Traditional Cheeses: A Review on Geographical Origin Authentication Methods, Foods, 11 (2022) 3379. DOI: 10.3390/foods11213379
Yaeko Suzuki, Achieving Food Authenticity and Traceability Using an Analytical Method Focusing on Stable Isotope Analysis, Anal. Sci., 37 (2021) 189-199. DOI: 10.2116/analsci.20SAR14
Application area: Medical/biological studies
Matthias Wiggenhauser, Rebekah E.T. Moore, Peng Wang, Gerd Patrick Bienert, Kristian Holst Laursen, Simon Blotevogel, Stable Isotope Fractionation of Metals and Metalloids in Plants: A Review, Front. Plant Sci., 13 (2022) 840941. DOI: 10.3389/fpls.2022.840941
Frank Vanhaecke, Marta Costas-Rodríguez, High-precision isotopic analysis of essential mineral elements: capabilities as a diagnostic/prognostic tool, View, 2/1 (2020) e91. DOI: 10.1002/VIW.20200094
Wolf D. Lehmann, A timeline of stable isotopes and mass spectrometry in the life sciences, Mass Spectrometry Reviews, 36 (2017) 58–85. DOI 10.1002/mas.21497
Francis Albarede, Philippe Telouk, Vincent Balter, Victor P. Bondanese, Emmanuelle Albalat, Philippe Oger, Paola Bonaventura, Pierre Miossec, Toshiyuki Fujii, Medical applications of Cu, Zn, and S isotope effects, Metallomics, 8 (2016) 1056-1070. DOI: 10.1039/c5mt00316d
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
Ilia Rodushkin, Emma Engström, Douglas C. Baxter, Isotopic analyses by ICP-MS in clinical samples, Anal. Bioanal. Chem., 405 (2013) 2785–2797. DOI: 10.1007/s00216-012-6457-x
Thomas Walczyk, The Use of Stable Isotope Techniques for Studying Mineral and Trace Element Metabolism in Humans, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 435-494. DOI: 10.1002/9783527650484.ch16
Application area: Forensic sciences
Johanna Irrgeher, Donata Bandoniene, Thomas Prohaska, Elemental and Isotopic Analyses in Forensic Sciences, in: Robert A. Meyer, Encyclopedia of Analytical Chemistry, John Wiley & Sons, 2020. DOI: 10.1002/9780470027318.a9440.pub2
Martin Resano, Frank Vanhaecke, Forensic Applications, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis:
Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012,
391-418. DOI: 10.1002/9783527650484.ch14
Sarah Benson, Chris Lennard, Philip Maynard, Claude Roux, Forensic applications of isotope ratio mass spectrometry—A review, Forensic Science International 157 (2006) 1–22. DOI: 10.1016/j.forsciint.2005.03.012
Application area: Environmental sciences
Johanna Irrgeher, Thomas Prohaska, Application of non-traditional stable isotopes in analytical ecogeochemistry assessed by MC ICP-MS - A critical review, Anal. Bioanal. Chem., 408 (2016) 369–385. DOI: 10.1007/s00216-015-9025-3
Jan G. Wiederhold, Metal Stable Isotope Signatures as Tracers in Environmental Geochemistry, Environ. Sci. Technol., 49 (2015) 2606−2624. DOI: 10.1021/es504683e
Kurt Kyser, Isotopes as Tracers of Elements Across the Geosphere–Biosphere Interface, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 351-372. DOI: 10.1002/9783527650484.ch12
D. Malinovsky, F. Vanhaecke, Mass-independent isotope fractionation of heavy elements measured by MC-ICPMS: a unique probe in environmental sciences, Anal. Bioanal. Chem., 400 (2011) 1619–1624. DOI: 10.1007/s00216-011-4856-z
Application area: Nuclear forensics
Kyuseok Song, Jong-Ho Park, Chi-Gyu Lee, Sun-Ho Han, Recent Developments in Nuclear Forensic and Nuclear Safeguards Analysis Using Mass Spectrometry, Mass Spectrom. Lett., 7/2 (2016) 31-40. DOI: 10.5478/MSL.2016.7.2.31
Scott C. Szechenyi and Michael E. Ketterer, Nuclear Applications, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 419-434. DOI: 10.1002/9783527650484.ch15
F. E. Stanley, A beginner’s guide to uranium chronometry in nuclear forensics and safeguards, J. Anal. At. Spectrom., 2012, 27, 1821-1830. DOI: 10.1039/c2ja30182b
Steven Goderis, Ramananda Chakrabarti, Vinciane Debaille, János Kodolányi, Isotopes in cosmochemistry: recipe for a Solar System, J. Anal. At. Spectrom., 31 (2016) 841-862. DOI: 10.1039/c5ja00411j
Mark Rehkämper, Maria Schönbächler, Rasmus Andreasen, Application of Multiple-Collector Inductively Coupled Plasma Mass Spectrometry to Isotopic Analysis in Cosmochemistry, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 275-315. DOI: 10.1002/9783527650484.ch10
Marlina A. Elburg, Geochronological Dating, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 235-274. DOI: 10.1002/9783527650484.ch9
Laura E. Wasylenki, Establishing the Basis for Using Stable Isotope Ratios of Metals as Paleoredox Proxies, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 317-350. DOI: 10.1002/9783527650484.ch11
Application area: Archeometry
Patrick Degryse, Archeometric Applications, in: Frank Vanhaecke, Patrick Degryse (eds.), Isotopic Analysis: Fundamentals and Applications Using ICP-MS, Wiley-VCH, Weinheim, 2012, 373-390. DOI: 10.1002/9783527650484.ch13
Special focus on single elements:
Daniel E. Bütz, Shanon L. Casperson, Leah D. Whigham, The emerging role of carbon isotope ratio determination in health research and medical diagnostics, J. Anal. At. Spectrom., 29 (2014) 594-598. DOI: 10.1039/c3ja50327e
Ramananda Chakrabarti, Surajit Mondal, Andrew D. Jacobson, Mark Mills, Stephen J. Romaniello, Hauke Vollstaedt, Review of techniques, challenges, and new developments for calcium isotope ratio measurements, Chem. Geol., 581 (2021) 120398. DOI: 10.1016/j.chemgeo.2021.120398
Ying Li a,1, Yi Huang a,b,1,*, Zijing Li a, Xue Tang a, Xiaowen Liu a, Scott S. Hughes, Mechanisms of chromium isotope fractionation and the applications in the environment, Ecotoxicol. Environ. Saf., 242 (2022) 113948. DOI: 10.1016/j.ecoenv.2022.113948
Kaj V. Sullivan, James A. Kidder, Tassiane P. Junqueira, Frank Vanhaecke, Matthew I. Leybourne, Emerging applications of high-precision Cu isotopic analysis by MC-ICP-MS, Sci. Total Environ., (2022) 156084. DOI: 10.1016/j.scitotenv.2022.156084
Rex N. Taylor, Osamu Ishizuka, Agnieszka Michalik, J. Andrew Miltona, Ian W. Croudace, Evaluating the precision of Pb isotope measurement by mass spectrometry, J. Anal. At. Spectrom., 30 (2015) 198-213. DOI: 10.1039/c4ja00279b
Hefa Cheng, Yuanan Hu, Lead (Pb) isotopic fingerprinting and its applications in lead pollution studies in China: A review, Environmental Pollution 158 (2010) 1134–1146. DOI: 10.1016/j.envpol.2009.12.028
Malin E. Kylander, Jonatan Klaminder, Richard Bindler, Dominik J. Weiss, Natural lead isotope variations in the atmosphere, Earth and Planetary Science Letters 290 (2010) 44–53. DOI: 10.1016/j.epsl.2009.11.055
Yajun An, Fang Huang, A Review of Mg Isotope Analytical Methods by MC-ICP-MS, J. Earth Sci., 25/5 (2014) 822–840. DOI: 10.1007/s12583-014-0477-8
Martin Tsz-Ki Tsui, Joel D. Blum, Sae Yun Kwon, Review of stable mercury isotopes in ecology and biogeochemistry, Sci. Total Environ., 716 (2020) 135386. DOI: 10.1016/j.scitotenv.2019.135386
Joel D. Blum, Marcus W. Johnson, Recent Developments in Mercury Stable Isotope Analysis, Rev. Mineral. Geochem., 82 (2017) 733-757. DOI: 10.2138/rmg.2017.82.17
Runsheng Yin, Xinbin Feng, Xiangdong Li, Ben Yu, Buyun Du, Trends and advances in mercury stable isotopes as a geochemical tracer, Trends Environ. Anal. Chem., 2 (2014) 1–10. DOI: 10.1016/j.teac.2014.03.001
Joel D. Blum, Applications of Stable Mercury Isotopes to Biogeochemistry, in: M. Baskaran (ed.), Handbook of Environmental Isotope Geochemistry, Advances in Isotope Geochemistry, Springer, 2011, 229-245. DOI 10.1007/978-3-642-10637-8_12
Xidong Liu, Yang Shao, Min Luo, Lingling Ma, Gang Xu, Minghong Wu, Progress of the Analytical Methods and Application of Plutonium Isotopes in the Environment, Processes, 11 (2023) 1430. DOI: 10.3390/pr11051430
Ines Coelho, Isabel Castanheira, Joao Moura Bordado, Olivier Donard, José Armando L. Silva, Recent developments and trends in the application of strontium and its isotopes in biological related fields, Trends Anal. Chem., 90 (2017) 45-61. DOI: 10.1016/j.trac.2017.02.005
Jie Lin, Yongsheng Liu, Haihong Chen, Lian Zhou, Zhaochu Hu, Shan Gao, Review of High-Precision Sr Isotope Analyses of Low-Sr Geological Samples, J. Earth Sci., 26/5 (2015) 763–774. DOI: 10.1007/s12583-015-0593-0
Further chapters on techniques and methodology for speciation analysis: