title: Proposed Guidelines for Solid Phase Extraction of Suwannee River Dissolved Organic Matter.
abstract: This paper proposes improved guidelines for dissolved organic matter (DOM) isolation by solid phase extraction (SPE) with a styrene-divinylbenzene copolymer (PPL) sorbent, which has become an established method for the isolation of DOM from natural waters, because of its ease of application and appreciable carbon recovery. Suwannee River water was selected to systematically study the effects of critical SPE variables such as loading mass, concentration, flow rate, and up-scaling on the extraction selectivity of the PPL sorbent. High-field Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and proton nuclear magnetic resonance ((1)H NMR) spectroscopy were performed to interpret the DOM chemical space of eluates, as well as permeates and wash liquids with molecular resolution. Up to 89% dissolved organic carbon (DOC) recovery was obtained with a DOC/PPL mass ratio of 1:800 at a DOC concentration of 20 mg/L. With the application of larger loading volumes, low proportions of highly oxygenated compounds were retained on the PPL sorbent. The effects of the flow rate on the extraction selectivity of the sorbent were marginal. Up-scaling had a limited effect on the extraction selectivity with the exception of increased self-esterification with a methanol solvent, resulting in methyl ester groups. Furthermore, the SPE/PPL extract exhibited highly authentic characteristics in comparison with original water and reverse osmosis samples. These findings will be useful for reproducibly isolating DOM with representative molecular compositions from various sources and concentrations and minimizing potential inconsistencies among interlaboratory comparative studies.
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.|Chair of Analytical Food Chemistry, Technische Universität München , 85354 Freising, Germany.
authors.forename: Mourad
authors.initials: M
authors.lastname: Harir
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Marianna
authors.initials: M
authors.lastname: Lucio
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Basem
authors.initials: B
authors.lastname: Kanawati
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Kirill
authors.initials: K
authors.lastname: Smirnov
authors.affiliation: GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany.
authors.forename: Ruth
authors.initials: R
authors.lastname: Flerus
authors.affiliation: Alfred Wegener Institute for Polar und Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany.|Hochschule Bremerhaven, University of Applied Sciences , An der Karlstadt 8, 27568 Bremerhaven, Germany.
authors.forename: Boris P
authors.initials: BP
authors.lastname: Koch
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.|Chair of Analytical Food Chemistry, Technische Universität München , 85354 Freising, Germany.
authors.forename: Philippe
authors.initials: P
authors.lastname: Schmitt-Kopplin
authors.affiliation: Research Unit Analytical Biogeochemistry (BGC), Helmholtz Zentrum München, German Research Center for Environmental Health , Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Hertkorn