Skip to content

Research at St Andrews

Triple oxygen isotope analysis of nitrate using isotope exchange - cavity ringdown laser spectroscopy

Research output: Contribution to journalArticle

DOI

Open Access Status

  • Embargoed (until 7/10/19)

Abstract

Rationale: Triple oxygen isotopes (16O/17O/18O) in nitrate are a valuable tool to ascertain the pathways of nitrate formation in the atmosphere and the fate of nitrate in ecosystems. Here we present a new method for determining Δ17O values in nitrates, based on nitrate-water isotope equilibration (IE) and subsequent isotopic analysis of water using cavity ringdown laser spectroscopy (CRDS).

Methods:  Nitrate oxygen (O-NO3-) is equilibrated with water oxygen (O-H2O) at low pH and 80oC. Subsequently, the δ17O and δ18O values of equilibrated water are determined by CRDS, scaled to V-SMOW and V-SLAP and calibrated against nitrate standards (USGS-34, USGS-35 and IAEA-NO3). We provide isotopic measurements of synthetic and natural nitrates and a direct inter-lab with the classic method of thermal-decomposition of nitrate followed by isotope ratio mass spectrometry of O2 (TD-IRMS).
Results: For synthetic NaNO3, the precision (1SD) of the IE-CRDS method is 0.8‰ for δ17O values, 1.7‰ for δ18O values and 0.2‰ for Δ17O values when using a O-NO3-/O-H2O greater than 0.0114±0.0001 (e.g. 12 μmol of NO3- in 50 μL of acid solution). For natural samples, after purification of nitrates by column chemistry and reprecipitation as AgNO3, the precision is better than 1.8‰ for δ17O values, 3.2‰ for δ18O values and 1‰ for Δ17O values. IE-CRDS and TD-IRMS yield Δ17O values within the analytical errors of the two methods. Conclusions The IE-CRDS method for determining Δ17O values in nitrates utilizes a user-friendly and relatively cheaper benchtop analytical instrument, representing an alternative to IRMS-based methods for certain applications.
Close

Details

Original languageEnglish
Pages (from-to)1949-1961
JournalRapid Communications in Mass Spectrometry
Volume32
Issue number22
Early online date7 Oct 2018
DOIs
Publication statusPublished - 30 Nov 2018

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. Indigenous organic-oxidized fluid interactions in the Tissint Mars meteorite

    Jaramillo, E. A., Royle, S. H., Claire, M. W., Kounaves, S. P. & Sephton, M. A., 28 Mar 2019, In : Geophysical Research Letters. 46, 6, p. 3090-3098

    Research output: Contribution to journalArticle

  2. Long-term planetary habitability and the carbonate-silicate cycle

    Rushby, A. J., Johnson, M., Mills, B. J. W., Watson, A. J. & Claire, M. W., 1 May 2018, In : Astrobiology. 18, 5, p. 469-480 12 p.

    Research output: Contribution to journalArticle

  3. Two-billion-year-old evaporites capture Earth's great oxidation

    Blättler, C., Claire, M., Prave, A. R., Zerkle, A. L. & Warke, M. R., 22 Mar 2018, In : Science. eaar2687.

    Research output: Contribution to journalArticle

  4. Evaluation of the Tindouf Basin region in Southern Morocco as an analog site for soil geochemistry on Noachian Mars

    Oberlin, E. A., Claire, M. W. & Kounaves, S., 9 Feb 2018, In : Astrobiology. 18, 8

    Research output: Contribution to journalArticle

  5. High-frequency fluctuations in redox conditions during the latest Permian mass extinction

    Mettam, C., Zerkle, A. L., Claire, M. W., Izon, G., Junium, C. J. & Twitchett, R. J., 1 Nov 2017, In : Palaeogeography, Palaeoclimatology, Palaeoecology. 485, p. 210-223

    Research output: Contribution to journalArticle

Related by journal

  1. Rapid Communications in Mass Spectrometry (Journal)

    Nora Nell Hanson (Reviewer)
    Dec 2011

    Activity: Publication peer-review and editorial work typesPeer review of manuscripts

Related by journal

  1. Changes in stable isotope compositions during fasting in phocid seals

    Habran, S., Damseaux, F., Pomeroy, P., Debier, C., Crocker, D., Lepoint, G. & Das, K., 30 Jan 2019, In : Rapid Communications in Mass Spectrometry. 33, 2, p. 176-184 9 p.

    Research output: Contribution to journalArticle

  2. Matrix-free mass spectrometric imaging using laser desorption ionisation Fourier transform ion cyclotron resonance mass spectrometry

    Goodwin, R. J. A., Pitt, A. R., Harrison, D., Weidt, S. K., Langridge-Smith, P. R. R., Barrett, M. P. & Logan Mackay, C., 2011, In : Rapid Communications in Mass Spectrometry. 25, 7, p. 969-972 4 p.

    Research output: Contribution to journalArticle

  3. Recovery of organic matter from mineral-rich sediment and soils for stable isotope analyses using static dense media

    Wurster, C. M., Saiz, G., Calder, A. & Bird, M. I., 15 Jan 2010, In : Rapid Communications in Mass Spectrometry. 24, 1, p. 165-168 4 p.

    Research output: Contribution to journalArticle

ID: 255553860