Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1021/acs.analchem.0c04426
Volltext Autorenversion
Titel (primär) Online counter gradient LC-FT-ICR-MS enables detection of highly polar natural organic matter fractions
Autor Han, L.; Kaesler, J.; Peng, C.; Reemtsma, T.; Lechtenfeld, O.J.
Journal / Serie Analytical Chemistry
Erscheinungsjahr 2021
Department ANA
Band/Volume 93
Heft 3
Seite von 1740
Seite bis 1748
Sprache englisch
Topic T9 Healthy Planet
UFZ Querschnittsthemen ProVIS
Abstract Natural organic matter (NOM) is a highly complex mixture of natural organic molecules. The recent developments in NOM molecular characterization methods have shown that ESI-FT-ICR hyphenated with liquid chromatography (LC) is a promising approach to also obtain chemical information (such as polarity and molecular size) about NOM molecules. However, due to changing solvent composition during gradient elution in LC-FT-ICR-MS, ionization conditions also change throughout the chromatographic separation process. In this study, we applied a post-LC column counter gradient (CG) to ensure stable solvent conditions for transient ESI-MS signals. Suwanee River Fulvic Acid (SRFA) standard and a peat pore water were used as representative dissolved NOM samples for method development and validation. Our results show that in polar NOM fractions (which elute with <50% methanol) the TIC intensity and number of assigned molecular formulas were increased by 48% and 20%, as compared to the standard gradient (SG) method. Further application of a Q-isolation and selective ion accumulation for low abundance fractions revealed over 3 times more molecular formulas (especially for CHNO, CHOS, CHNOS formula classes) than in full scan mode. The number of detected highly polar NOM compounds (with elemental ratios H/C < 1, O/C > 0.6) were more than 20 times larger for CG-LC mode as compared to direct infusion (DI) (5715 vs 266 MF). We conclude that the application of a postcolumn counter gradient in LC-FT-ICR-MS analyses of NOM offers novel insight into the most polar fractions of NOM which are inaccessible in conventional DI measurements.
dauerhafte UFZ-Verlinkung
Han, L., Kaesler, J., Peng, C., Reemtsma, T., Lechtenfeld, O.J. (2021):
Online counter gradient LC-FT-ICR-MS enables detection of highly polar natural organic matter fractions
Anal. Chem. 93 (3), 1740 - 1748