Isotope Ratio Mass Spectrometry

Instrumentation in the lab for Compound-Specific Isotope Analysis.

Compound-Specific Isotope Analysis using Gas Chromatography- Isotope Ratio Mass Spectrometry (GC-IRMS) and Liquid Chromatography-Isotope Ratio Mass Spectrometry (LC-IRMS)

To implement the research aims of our group, Compound-Specific Isotope Analysis (CSIA) is used as an analytical tool to receive information on natural isotope abundances of 13C/12C, 15N/14N, 2H/1H, 37Cl/35Cl. CSIA is accomplished by the hyphenation of either a gas chromatograph (GC) or a liquid chromatograph (LC) with an isotope ratio mass spectrometer (IRMS) according to the following principle:



  • Development of new analytical methods for pesticides, pharmaceuticals and chlorinated compounds (see publications below-link) for analyses of isotope compositions in degradation experiments and field samples

  • Development of chlorinated reference materials for Cl and C isotope analysis

  • Routine isotope analyses of organic contaminants (aromatic hydrocarbons, chlorinated hydrocarbons) in cooperation with our spin-up company Isodetect GmbH

Bulk Isotope Analysis by Elemental Analyzer (EA)-IRMS and Dual-Inlet-IRMS

  • Chemical conversion (online or offline combustion or pyrolysis) into a measurement gas (CO2, N2, H2, SO2, CO)

  • Determination of natural isotope ratios (13C/12C; 15N/ 14N; 2H/1H, 18O/16O, 34S/32S) of nitrate, nitrite, sulfate, sulfite, sulfide, water, organic compounds

  • Participation in international proficiency (ring-tests) tests

  • Standardization of internal laboratory-reference materials


  • E. O. Mogusu, B.J. Wolbert, D. M. Kujawinski, M. A. Jochmann, M. Elsner, Dual element (15N/14N, 13C/12C) isotope analysis of glyphosate and AMPA by derivatization-gas chromatography isotope ratio mass spectrometry (GC/IRMS) combined with LC/IRMS; Analytical and bioanalytical chemistry (2015): 1-12.
  • M. P. Maier, S. Qiu, M. Elsner, Enantioselective stable isotope analysis (ESIA) of polar herbicides; Analytical and Bioanalytical Chemistry, (2013), 405, (9), 2825-2831.
  • K. Schreglmann, M. Hoeche, S. Steinbeiss, S. Reinnicke, M. Elsner, Carbon and Nitrogen Isotope Analysis of Atrazine and dethylatrazine at Sub-µg/L Concentrations in Groundwater; Analytical and Bioanalytical Chemistry, (2013) DOI 10.1007/s00216-012-6616-0
  • S. Spahr, S. Huntscha, J. Bolotin, M. P. Maier, M. Elsner, J. Hollender, T. B. Hofstetter, Compound-specic isotope analysis of benzotriazole and its derivatives; Analytical and Bioanalytical Chemistry (2013) DOI 10.1007/s00216-012-6526-1
  • M. Elsner, M. A. Jochmann, T. B. Hofstetter, D. Hunkeler, A. Bernstein, T. C. Schmidt, A. Schimmelmann, Current challenges in compound-specific stable isotope analysis of environmental organic contaminants, Analytical and Bioanalytical Chemistry, 403 (2012), 2471–2491.
  • S. Reinnicke, D. Juchelka, S. Steinbeiss, A. Meyer, A. Hilkert, M. Elsner, Gas chromatography-isotope ratio mass spectrometry (GC-IRMS) of recalcitrant target compounds: performance of different combustion reactors and strategies for standardization, Rapid Communications in Mass Spectrometry, 26 (2012), 1053–1060.
  • A. Bernstein, O. Shouakar-Stash, K. Ebert, C. Laskov, D. Hunkeler, S. Jeannottat, K. Sakaguchi-Söder, J. Laaks, M. A. Jochmann, S. Cretnik, J. Jager, S. B. Haderlein, T. C. Schmidt, R. Aravena, M. Elsner, Compound-Specific Chlorine Isotope Analysis: A Comparison of Gas Chromatography/Isotope Ratio Mass Spectrometry and Gas Chromatography/Quadrupole Mass Spectrometry Methods in an Interlaboratory Study, Analytical Chemistry, 83 (2011), 7624–7634.
  • M. Elsner, Stable Isotope Fractionation to Investigate Natural Transformation Mechanisms of Organic Contaminants: Principles, Prospects and Limitations, Journal of Environmental Monitoring, 12 (2010), 2005-2031
  • S. Reinnicke, A. Bernstein, M. Elsner, Small and Reproducible Isotope Effects during Methylation with Trimethylsulfonium Hydroxide (TMSH): A Convenient Derivatization Method for Isotope Analysis of Negatively Charged Molecules, Analytical Chemistry, 82 (2010), 2013-2019.
  • A.H. Meyer, H. Penning, H. Lowag, M. Elsner, Precise and Accurate Compound Specific Carbon and Nitrogen Isotope Analysis of Atrazine: Critical Role of Combustion Oven Conditions, Environmental Science & Technology, 42 (2008), 7757-776
  • H. Penning and M. Elsner, Intramolecular Carbon and Nitrogen Isotope Analysis by Quantitative Dry Fragmentation of the Phenylurea Herbicide Isoproturon in a Combined Injector/Capillary Reactor prior to GC Separation, Analytical Chemistry, 79 (2007), 8399-8405