Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1021/acs.est.3c07219
Licence creative commons licence
Title (Primary) Direct analysis of marine dissolved organic matter using LC-FT-ICR MS
Author Lechtenfeld, O.J. ORCID logo ; Kaesler, J.; Jennings, E.K.; Koch, B.P.
Source Titel Environmental Science & Technology
Year 2024
Department EAC
Volume 58
Issue 10
Page From 4637
Page To 4647
Language englisch
Topic T9 Healthy Planet
Data and Software links
Keywords Natural organic matter Salt water RP-LC-MS Fourier transform ion cyclotron resonance mass spectrometry PPL, SPE
UFZ wide themes ProVIS;
Abstract Marine dissolved organic matter (DOM) is an important component of the global carbon cycle, yet its intricate composition and the sea salt matrix pose major challenges for chemical analysis. We introduce a direct injection, reversed-phase liquid chromatography ultrahigh resolution mass spectrometry approach to analyze marine DOM without the need for solid-phase extraction. Effective separation of salt and DOM is achieved with a large chromatographic column and an extended isocratic aqueous step. Postcolumn dilution of the sample flow with buffer-free solvents and implementing a counter gradient reduced salt buildup in the ion source and resulted in excellent repeatability. With this method, over 5,500 unique molecular formulas were detected from just 5.5 nmol carbon in 100 μL of filtered Arctic Ocean seawater. We observed a highly linear detector response for variable sample carbon concentrations and a high robustness against the salt matrix. Compared to solid-phase extracted DOM, our direct injection method demonstrated superior sensitivity for heteroatom-containing DOM. The direct analysis of seawater offers fast and simple sample preparation and avoids fractionation introduced by extraction. The method facilitates studies in environments, where only minimal sample volume is available e.g. in marine sediment pore water, ice cores, or permafrost soil solution. The small volume requirement also supports higher spatial (e.g., in soils) or temporal sample resolution (e.g., in culture experiments). Chromatographic separation adds further chemical information to molecular formulas, enhancing our understanding of marine biogeochemistry, chemodiversity, and ecological processes.
Persistent UFZ Identifier
Lechtenfeld, O.J., Kaesler, J., Jennings, E.K., Koch, B.P. (2024):
Direct analysis of marine dissolved organic matter using LC-FT-ICR MS
Environ. Sci. Technol. 58 (10), 4637 - 4647 10.1021/acs.est.3c07219