JEOL joined a host of scientists flocking to the Bay Area August 13 – 17, 2023 to attend ACS Fall 2023: Harnessing the Power of Data. Each year, the American Chemical Society hosts two major conferences for chemists around the country, as well as smaller regional events.
This year, ACS Fall attracted more than 15,000 attendees from more than 80 countries around the globe. Scientists from academic institutions, government agencies, and the manufacturing sector were represented largely by people traveling within the US but also from Korea, China, the UK, and Canada.
JEOL maintained a presence in booth 637 with representatives from our mass spectrometry and electron optics product groups.
Division of Analytical Chemistry Presentation:
Sunday morning JEOL Applications Scientist Dr. Kirk Jensen gave an oral presentation titled Chromatographic Deconvolution and Automated Data Analysis for Non-Targeted MS Coupled with Fast Separation by LPGC. In this talk, Dr. Jensen offered a solution to rapidly identify unknown pesticides from a complex sample using
GC-QMS and
msFineAnalysis iQ.
To demonstrate the effectiveness of msFineAnalysis iQ, a sample mixture containing 256 pesticides was measured by GC-QMS. To test the peak deconvolution feature, a low-pressure GC column was used, which reduces GC time by using the vacuum of the MS and a large diameter GC column at a minor sacrifice to separation efficiency. For SI measurements, chemical ionization, photoionization, and low-energy EI were tested. Over 60% of the pesticides were identified correctly by matching library spectra, RI, isotope ratios, and molecular ions. Approximately 20 percent of the pesticides were observed but could not be identified automatically due to almost complete coelution. Twenty percent of the compounds were not observed, even though their presence was confirmed by
TQ-MS.
Division of Energy and Fuels Presentation:
Then, on Monday afternoon, Principal Scientist Dr. Robert “Chip” Cody presented “Comprehensive Two-Dimensional Gas Chromatography (GCxGC) Coupled with Soft Ionization Time-of-Flight Mass Spectrometry for Petroleum Type Analysis and biomarker identification.”
Although traditional electron ionization (EI) provides mass spectra that can be searched against databases, there are limitations. Molecular ions are not observed for many compounds. In addition, isotope peaks for fragment ions can interfere with the two-dimensional selected ion chromatograms for biomarker families such as hopanes and cholestanes. Soft ionization techniques, like FI, PI, and CI, however, can fill the gap.
Through his research, Dr. Cody demonstrated the advantages of each of these ionization techniques using the
AccuTOF™ GC-Alpha. Field ionization produces primarily molecular ions with little or no fragmentation. Photoionization produces molecular ions for most compound classes with some fragmentation that can aid in the identification of biomarker families and the structural analysis of branched hydrocarbons. Chemical ionization is more sensitive than either FI or PI, but molecular weight identification can be complicated by fragments and adducts.
When analyzing energy and fuels, field ionization is particularly useful because it produces molecular ions with little or no fragmentation. This greatly simplifies the task of identifying compound classes in the GCxGC-MS chromatograms, and it eliminates artifacts in the chromatograms for petroleum biomarkers.
Stay Connected:
To continue the conversation with JEOL, you can explore our mass spectrometry solutions on our
website, or
contact your local sales representative.
We’ll be at ACS Spring 2024 “The Many Flavors of Chemistry” in New, Orleans, so stop by if you see us!