title: Capillary ion chromatography with on-column focusing for ultra-trace analysis of methanesulfonate and inorganic anions in limited volume Antarctic ice core samples.
abstract: Preservation of ionic species within Antarctic ice yields a unique proxy record of the Earth's climate history. Studies have been focused until now on two proxies: the ionic components of sea salt aerosol and methanesulfonic acid. Measurement of the all of the major ionic species in ice core samples is typically carried out by ion chromatography. Former methods, whilst providing suitable detection limits, have been based upon off-column preconcentration techniques, requiring larger sample volumes, with potential for sample contamination and/or carryover. Here, a new capillary ion chromatography based analytical method has been developed for quantitative analysis of limited volume Antarctic ice core samples. The developed analytical protocol applies capillary ion chromatography (with suppressed conductivity detection) and direct on-column sample injection and focusing, thus eliminating the requirement for off-column sample preconcentration. This limits the total sample volume needed to 300μL per analysis, allowing for triplicate sample analysis with <1mL of sample. This new approach provides a reliable and robust analytical method for the simultaneous determination of organic and inorganic anions, including fluoride, methanesulfonate, chloride, sulfate and nitrate anions. Application to composite ice-core samples is demonstrated, with coupling of the capillary ion chromatograph to high resolution mass spectrometry used to confirm the presence and purity of the observed methanesulfonate peak.
authors.affiliation: Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia.
authors.forename: Estrella Sanz
authors.initials: ES
authors.lastname: Rodriguez
authors.affiliation: Antarctic Climate and Ecosystems Cooperative Research Centre, GPO Box 252-80, Hobart, Tasmania 7001, Australia.
authors.forename: Sam
authors.initials: S
authors.lastname: Poynter
authors.affiliation: Antarctic Climate and Ecosystems Cooperative Research Centre, GPO Box 252-80, Hobart, Tasmania 7001, Australia; Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania 7050, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Curran
authors.affiliation: Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Haddad
authors.affiliation: Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Shellie
authors.affiliation: Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia.
authors.forename: Pavel N
authors.initials: PN
authors.lastname: Nesterenko
authors.affiliation: Australian Centre for Research on Separation Science, School of Physical Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia. Electronic address: Brett.Paull@utas.edu.au.
authors.forename: Brett
authors.initials: B
authors.lastname: Paull
mesh_terms: D000838:Anions; D000864:Antarctic Regions; D002712:Chlorides / Q000032:analysis; D002852:Chromatography, Ion Exchange / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods; D005459:Fluorides / Q000032:analysis; D007053:Ice / Q000032:analysis*; D013058:Mass Spectrometry; D008698:Mesylates / Q000032:analysis*; D009566:Nitrates / Q000032:analysis; D013431:Sulfates / Q000032:analysis
chemical_list: D000838:Anions; D002712:Chlorides; D007053:Ice; D008698:Mesylates; D009566:Nitrates; D013431:Sulfates; C045880:methanesulfonic acid; D005459:Fluorides
keywords: Antarctic ice cores; Capillary ion chromatography; IC-MS; Inorganic anions; Methanesulfonic acid; On-column focussing