Mass Spectrometry for Organic Matter Analysis
Organic matter is a complex, heterogenous mixture important in natural environmental systems, playing a key role in carbon and nutrient cycling. Analysis of organic matter can use many techniques, each delivering key information. Only high-resolution mass spectrometry (MS) has the sensitivity and resolution to identify the thousands of molecules present. Fourier transform ion cyclotron resonance (FTICR) MS is one of EMSL’s major strengths, delivering the highest achievable mass resolution and accuracy, making it an invaluable part of the analysis of organic matter.
EMSL’s mix of commercial and custom-built FTICR MS instrumentation supports many aspects of organic matter analysis, including organic carbon characterization or metal-organic matter binding studies. These efforts yield great insight into mechanistic and predictive understanding of environmental processes above and belowground, on Earth, and in aqueous environments.
Research application
- Supporting the Biogeochemical Transformation Integrated Research Platform, these resources provide rich data for organic matter characterization, supporting modeling of complex environmental or ecological processes and systems.
- Supporting the Biomolecular Pathways Integrated Research Platform, these resources can also provide key data for understanding biological pathways, including metabolic processes, by studying the changes or organic matter induced by microbial or plant activity.
Available instruments
- EMSL 21 Tesla FTICR MS: Hybrid Q-FT Orbitrap–Ion Cyclotron Resonance mass spectrometer consists of a Thermo Scientific™ Orbitrap Exploris™ 480, coupled to a custom-built 21T Fourier Transform Ion Cyclotron Resonance (FTICR) mass spectrometer. EMSL’s 21T FTICR, which has the highest available magnetic field, enables ultra-high mass resolution and mass accuracy measurements for the most complex samples. Dual high resolution mass analyzers allow for parallel precursor and fragment ion mass spectrometry measurements with the highest mass accuracy and resolution.
- This mass spectrometer supports
- electrospray ionization (ESI)
- atmospheric pressure chemical ionization (APCI)
- atmospheric pressure photoionization (APPI)
- nanospray desorption electrospray ionization (nanoDESI)
- liquid extraction surface analysis (LESA)
- laser-ablation electrospray ionization (LAESI).
- The 21T is suitable for direct infusion, liquid chromatography, and mass spectrometry imaging. The mass spectrometer is equipped with a FTMS Booster X3T™ from Spectroswiss Inc. for advanced data acquisition.
- Bruker 12 Tesla SolariX XR: High-magnetic field instrument with dynamically harmonized cell, suitable for organic matter analyses and mass spectrometry imaging of plant, microbial, and tissue samples with its joint ESI/matrix assisted laser desorption ionization (MALDI) source. Also supports APPI.
- Bruker 7 Tesla scimaX MRMS: High resolution FTICR mass spectrometer suitable for the analysis of small molecules and complex mixtures, and mass spectrometry imaging studies using the dual ESI/MALDI source. Also supports APPI.
Tips for success
- Mass spectrometry is a highly sensitive technique, but minimum sample concentrations (i.e., total organic carbon levels) and volumes are necessary for success, as any trace contamination could obscure your sample.
- Mass spectrometry is susceptible to contamination, which may impede analysis, especially from polymers and salts. Discuss your sampling procedures and sample preparation protocols with your EMSL science point of contact as early as possible to ensure your best chances for success.
- Competitive ionization, or ionization suppression, means that data generated are not directly quantitative. Further, each ionization source—and other instrumental parameters—can induce bias into what is observed. It is important to remember what is seen is just part of what is likely present.
- In routine operation, the spectra recorded show thousands of molecular ions, with minimal fragmentation. High mass accuracy means it is possible to assign molecular formula to these species. However, formula is not structure and each peak may be several isomeric compounds.