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Updated: Aug 6, 2026
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Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry (UPLC-HRMS)
Published on: May 20, 2013
Chromatography Coupled to High-Resolution Mass Spectrometry Analysis Reveals Flaws in van Krevelen Compound Class
Maria G Digernes1, Alexander J Craig2, Tsz Yung Patrick Wong2,3
1Norwegian University of Science and Technology (NTNU) Department of Chemistry, Trondheim7049, Norway.
Environmental Science & Technology
|July 22, 2026
Summary
High-resolution mass spectrometry (HRMS) alone is insufficient for accurately identifying dissolved organic matter (DOM) origins. Combining liquid chromatography with HRMS reveals broad chemical diversity, challenging current DOM classification methods.
Area of Science:
- Environmental chemistry
- Biogeochemistry
- Analytical chemistry
Background:
- High-resolution mass spectrometry (HRMS) is widely used to determine molecular formulas in dissolved organic matter (DOM).
- Current methods often assign DOM molecular formulas to chemical classes based solely on elemental ratios, which can be inaccurate.
- DOM's complexity and HRMS's limitations in providing chemical connectivity information hinder precise molecular origin identification.
Purpose of the Study:
- To assess the consistency of biochemical class assignments with liquid chromatography-HRMS retention behavior.
- To investigate the chemical diversity within assigned DOM classes.
- To evaluate the utility of standard HRMS practices in DOM biogeochemical studies.
Main Methods:
- Utilized liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS).
- Analyzed retention profiles of various DOM compound classes.
- Compared experimental retention behavior with known hydrophobicity data and environmental sample characteristics.
Main Results:
- Observed broad retention profiles for all examined DOM classes, indicating significant chemical functionality diversity.
- Found poor agreement between retention behavior and established biochemical class hydrophobicity, especially for carbohydrates and peptides.
- Detected distinct differences in compound class and molecular formula retention profiles between terrestrial and marine DOM samples, highlighting environmental-specific isomer composition.
Conclusions:
- Standard practices of assigning DOM molecular formulas to prospective classes based on elemental ratios alone are questionable.
- Retention behavior analysis reveals greater chemical diversity within DOM classes than previously assumed.
- Integrating chromatography and tandem MS methods is crucial for a more accurate chemical understanding of DOM in biogeochemical research.
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