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.
- 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.
- EMSL 21 Tesla FTICR MS: Highest magnetic field instrument achieving highest resolution and mass accuracy for the most complex samples. Supports ESI, APPI/APCI, nano-spray, nano-DESI, and LAESI and MALDI-2 ionization sources, for direct infusion, LC, or mass spectrometry imaging.
- Bruker 15 Tesla SolariX XR: High magnetic field instrument suited to challenging samples, method development, and mass spectrometry imaging with its joint ESI/MALDI source. Also supports APPI.
- Bruker 12 Tesla SolariX: Established system for characterization of dissolved organic matter samples, supports direct infusion ESI with in-house built flow-injection analysis for continuous operation and high-throughput.
- Bruker 7 Tesla scimaX MRMS: High resolution FTICR mass spectrometer suitable for the analysis of small molecules and complex mixtures, and for mass spectrometry imaging studies thanks to 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.