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Stable Isotope Analysis of Intact Oxyanions Using Electrospray Quadrupole-Orbitrap Mass Spectrometry

Neubauer, Cajetan and Crémière, Antoine and Wang, Xingchen T. and Thiagarajan, Nivedita and Sessions, Alex L. and Adkins, Jess F. and Dalleska, Nathan F. and Turchyn, Alexandra V. and Clegg, Josephine A. and Moradian, Annie and Sweredoski, Michael J. and Garbis, Spiros D. and Eiler, John M. (2020) Stable Isotope Analysis of Intact Oxyanions Using Electrospray Quadrupole-Orbitrap Mass Spectrometry. Analytical Chemistry, 92 (4). pp. 3077-3085. ISSN 0003-2700. doi:10.1021/acs.analchem.9b04486.

[img] PDF (Overview of existing methods for sulfate and nitrate isotopic analysis (Table S1). Details of the sulfate and nitrate materials used in this study (Table S2), including their isotopic composition. Description of methods used for determining bulk...) - Supplemental Material
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The stable isotopes of sulfate, nitrate, and phosphate are frequently used to study geobiological processes of the atmosphere, ocean, as well as land. Conventionally, the isotopes of these and other oxyanions are measured by isotope-ratio sector mass spectrometers after conversion into gases. Such methods are prone to various limitations on sensitivity, sample throughput, or precision. In addition, there is no general tool that can analyze several oxyanions or all the chemical elements they contain. Here, we describe a new approach that can potentially overcome some of these limitations based on electrospray hyphenated with Quadrupole Orbitrap mass spectrometry. This technique yields an average accuracy of 1–2‰ for sulfate δ³⁴S and δ¹⁸O and nitrate δ¹⁵N and δ¹⁸O, based on in-house and international standards. Less abundant variants such as δ¹⁷O, δ³³S, and δ³⁶S, and the ³⁴S–¹⁸O “clumped” sulfate can be quantified simultaneously. The observed precision of isotope ratios is limited by the number of ions counted. The counting of rare ions can be accelerated by removing abundant ions with the quadrupole mass filter. Electrospray mass spectrometry (ESMS) exhibits high-throughput and sufficient sensitivity. For example, less than 1 nmol sulfate is required to determine ¹⁸O/³⁴S ratios with 0.2‰ precision within minutes. A purification step is recommended for environmental samples as our proposed technique is susceptible to matrix effects. Building upon these initial provisions, new features of the isotopic anatomy of mineral ions can now be explored with ESMS instruments that are increasingly available to bioanalytical laboratories.

Item Type:Article
Related URLs:
URLURL TypeDescription
Neubauer, Cajetan0000-0002-5348-5609
Crémière, Antoine0000-0001-7382-2097
Wang, Xingchen T.0000-0001-5316-789X
Sessions, Alex L.0000-0001-6120-2763
Adkins, Jess F.0000-0002-3174-5190
Dalleska, Nathan F.0000-0002-2059-1587
Turchyn, Alexandra V.0000-0002-9298-2173
Moradian, Annie0000-0002-0407-2031
Sweredoski, Michael J.0000-0003-0878-3831
Garbis, Spiros D.0000-0002-1050-0805
Additional Information:© 2020 American Chemical Society. Received: October 1, 2019; Accepted: January 21, 2020; Published: February 3, 2020. We thank the reviewers for comments. We are grateful for assistance provided by Roxana Eggleston-Rangel and Brett Lomenick, and thank George Rossmann as well as the companies Peñoles, Crimidesa, Saltex, Airborne Industrial Minerals, and Searles Valley Minerals for providing sulfates. This study was using ESMS instrumentation at the Proteome Exploration Laboratory (supported by Beckman Institute, and NIH 1S10OD02001301). C.N. is a fellow of the Hanse-Wissenschaftskolleg. The authors declare no competing financial interest.
Funding AgencyGrant Number
Caltech Beckman InstituteUNSPECIFIED
Issue or Number:4
Record Number:CaltechAUTHORS:20200204-073456000
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Official Citation:Stable Isotope Analysis of Intact Oxyanions Using Electrospray Quadrupole-Orbitrap Mass Spectrometry. Cajetan Neubauer, Antoine Crémière, Xingchen T. Wang, Nivedita Thiagarajan, Alex L. Sessions, Jess F. Adkins, Nathan F. Dalleska, Alexandra V. Turchyn, Josephine A. Clegg, Annie Moradian, Michael J. Sweredoski, Spiros D. Garbis, and John M. Eiler. Analytical Chemistry 2020 92 (4), 3077-3085; DOI: 10.1021/acs.analchem.9b04486
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:101096
Deposited By: Tony Diaz
Deposited On:04 Feb 2020 17:38
Last Modified:16 Nov 2021 17:59

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