Direct injection liquid chromatography high-resolution mass spectrometry for determination of primary and secondary terrestrial and marine biomarkers in ice cores

Many atmospheric organic compounds are long-lived enough to be transported from their sources to polar regions and high mountain environments where they can be trapped in ice archives. While inorganic components in ice archives have been studied extensively to identify past climate changes, organic...

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Bibliographic Details
Main Authors: King, Amy, Giorio, Chiara, Wolff, Eric, Thomas, Elizabeth, Roverso, Marco, Schwikowski, Margit, Tapparo, Andrea, bogialli, sara, Kalberer, Markus
Format: Article in Journal/Newspaper
Language:English
Published: American Chemical Society (ACS) 2019
Subjects:
Ice
Online Access:https://www.repository.cam.ac.uk/handle/1810/290987
https://doi.org/10.17863/CAM.38166
Description
Summary:Many atmospheric organic compounds are long-lived enough to be transported from their sources to polar regions and high mountain environments where they can be trapped in ice archives. While inorganic components in ice archives have been studied extensively to identify past climate changes, organic compounds have rarely been used to assess paleo-environmental changes, mainly due to the lack of suitable analytical methods. This study presents a new method of direct injection HPLC-MS analysis, without the need of pre-concentrating the melted ice, for the determination of a series of novel biomarkers in ice-core samples indicative of primary and secondary terrestrial and marine organic aerosol sources. Eliminating a preconcentration step reduces contamination potential and decreases the required sample volume thus allowing a higher time resolution in the archives. The method is characterised by limits of detections (LODs) in the range of 0.01-15 ppb, depending on the analyte, and accuracy evaluated through an interlaboratory comparison. We find that many components in secondary organic aerosols (SOA) are clearly detectable at concentrations comparable to those previously observed in replicate preconcentrated ice samples from the Belukha glacier, Russian Altai Mountains. Some compounds with low recoveries in preconcentration steps are now detectable in samples with this new direct injection method significantly increasing the range of environmental processes and sources that become accessible for paleo-climate studies. Work by Amy King was jointly supported by Selwyn College, Cambridge, and the NERC Doctoral Training Programme [grant number NE/L002507/1]. Work by Chiara Giorio was supported by the ‘BAS-UCAM Innovation Centre Feasibility Studies’ programme 2013-2015 [project ‘Organics in Ice’] and by the ERC Consolidator Grant 279405 “COrANE”. Eric Wolff was supported by a Royal Society Professorship.