Design and Evaluation of a Gas Chromatograph-Atmospheric Pressure Chemical Ionization Interface for an Exactive Orbitrap Mass Spectrometer

  • Joshua B. Powers
  • Shawn R. CampagnaEmail author
Research Article


Various separation and mass spectrometric (MS) techniques have furthered our ability to study complex mixtures, and the desire to measure every analyte in a system is of continual interest. For many complex mixtures, such as the total molecular content of a cell, it is becoming apparent that no one single separation technique or analysis is likely to achieve this goal. Therefore, having a variety of tools to measure the complexity of these mixtures is prudent. Orbitrap MSs are broadly used in systems biology studies due to their unique performance characteristics. However, GC-Orbitraps have only recently become available, and instruments that can use gas chromatography (GC) cannot use liquid chromatography (LC) and vice versa. This limits small molecule analyses, such as those that would be employed for metabolomics, lipidomics, or toxicological studies. Thus, a simple, temporary interface was designed for a GC and Thermo Scientific™ Ion Max housing unit. This interface enables either GC or LC separation to be used on the same MS, an Exactive™ Plus Orbitrap, and utilizes an atmospheric pressure chemical ionization (APCI) source. The GC-APCI interface was tested against a commercially available atmospheric pressure photoionization (APPI) interface for three types of analytes that span the breadth of typical GC analyses: fatty acid methyl esters (FAMEs), polyaromatic hydrocarbons (PAHs), and saturated hydrocarbons. The GC-APCI-Orbitrap had similar or improved performance to the APPI and other reported methods in that it had a lower limit of quantitation, better signal to noise, and lower tendency to fragment analytes.


Gas chromatography Atmospheric pressure chemical ionization (APCI) Atmospheric pressure chemical ionization (APPI) GC-MS Fatty acid methyl esters (FAMEs) Polyaromatic hydrocarbons (PAHs) Saturated hydrocarbons Interface Orbitrap 



The authors thank Mr. Tim Free and Mr. Danny Hackworth for the assistance in machining parts and Mr. Matthew Nalepa for the help with the electrical components of the interface. We also acknowledge Dr. Hector F. Castro (Biological and Small Molecule Mass Spectrometry Core, UTK) and Dr. Brandon J. Kennedy for the helpful discussions and instrumental assistance as well as the reviewers for their insightful commentary into the first draft of the manuscript. Mr. Joshua B. Powers was supported by NSF award MCB-1615373. Instrumentation was provided by both NSF award DBI-1530975 and the University of Tennessee Institute of Agriculture.

Supplementary material

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  1. 1.
    Wang, L., Xing, X., Chen, L., Yang, L., Su, X., Rabitz, H., Lu, W., Rabinowitz, J.D.: Peak Annotation and Verification Engine for Untargeted LC–MS Metabolomics. Anal. Chem. 91, 1838–1846 (2019)CrossRefGoogle Scholar
  2. 2.
    Peterson, A.C., Hauschild, J.-P., Quarmby, S.T., Krumwiede, D., Lange, O., Lemke, R.A.S., Grosse-Coosmann, F., Horning, S., Donohue, T.J., Westphall, M.S., Coon, J.J., Griep-Raming, J.: Development of a GC/Quadrupole-Orbitrap Mass Spectrometer, Part I: Design and Characterization. Anal. Chem. 86, 10036–10043 (2014)CrossRefGoogle Scholar
  3. 3.
    Weidt, S., Pesko, B., Cojocariu, C., Silcock, P., Burchmore, R.J., Burgess, K.: Untargeted Metabolomics Using Orbitrap-Based GC-MS.Google Scholar
  4. 4.
    Portolés, T., Sancho, J., Hernández, F., Newton, A., Hancock, P.: Potential of Atmospheric Pressure Chemical Ionization Source in GC-QTOF MS for Pesticide Residue Analysis. J. Mass Spectrom. 45, 926–936 (2010)CrossRefGoogle Scholar
  5. 5.
    Yan, Y., Rempel, D.L., Holy, T.E., Gross, M.L.: Mass Spectrometry Combinations for Structural Characterization of Sulfated-Steroid Metabolites. J. Am. Soc. Mass Spectrom. 25, 869–879 (2014)CrossRefGoogle Scholar
  6. 6.
    Jaeger, C., Tellström, V., Zurek, G., König, S., Eimer, S., Kammerer, B.: Metabolomic Changes in Caenorhabditis elegans Lifespan Mutants as Evident from GC–EI–MS and GC–APCI–TOF–MS profiling. Metabolomics. 10, 859–876 (2014)CrossRefGoogle Scholar
  7. 7.
    Kersten, H., Kroll, K., Haberer, K., Brockmann, K.J., Benter, T., Peterson, A., Makarov, A.: Design Study of an Atmospheric Pressure Photoionization Interface for GC-MS. J. Am. Soc. Mass Spectrom. 27, 607–614 (2016)CrossRefGoogle Scholar
  8. 8.
    Horning, E., Horning, M., Carroll, D., Dzidic, I., Stillwell, R.: New Picogram Detection System Based on a Mass Spectrometer with an External Ionization Source at Atmospheric Pressure. Anal. Chem. 45, 936–943 (1973)CrossRefGoogle Scholar
  9. 9.
    Zuth, C., Vogel, A.L., Ockenfeld, S., Huesmann, R., Hoffmann, T.: Ultrahigh-Resolution Mass Spectrometry in Real Time: Atmospheric Pressure Chemical Ionization Orbitrap Mass Spectrometry of Atmospheric Organic Aerosol. Anal. Chem. 90, 8816–8823 (2018)CrossRefGoogle Scholar
  10. 10.
    Holman, J.D., Tabb, D.L., Mallick, P.: Employing ProteoWizard to Convert Raw Mass Spectrometry Data. Curr. Protoc. Bioinformatics 46, 13.24. 11-13.24. 19 (2014)Google Scholar
  11. 11.
    Clasquin, M.F., Melamud, E., Rabinowitz, J.D.: LC-MS Data Processing with MAVEN: a Metabolomic Analysis and Visualization Engine. Curr. Protoc. Bioinformatics. 37, 14.11. 11–14.11. 23 (2012)Google Scholar
  12. 12.
    Lee, Y.J., Smith, E.A., Jun, J.H.: Gas Chromatography-High Resolution Tandem Mass Spectrometry Using a GC-APPI-LIT Orbitrap for Complex Volatile Compounds Analysis. Mass Spectro. Lett. 3, 29 (2012)Google Scholar
  13. 13.
    Dodds, E.D., McCoy, M.R., Rea, L.D., Kennish, J.M.: Gas Chromatographic Quantification of Fatty Acid Methyl Esters: Flame Ionization Detection vs. Electron Impact Mass Spectrometry. Lipids. 40, 419–428 (2005)CrossRefGoogle Scholar
  14. 14.
    Alawi, M.A., Abdullah, R.A., Tarawneh, I.: Determination of Polycyclic Aromatic Hydrocarbons (PAHs) in Carbon Black-Containing Plastic Consumer Products from the Jordanian Market. Toxin Rev. 37, 269–277 (2018)CrossRefGoogle Scholar
  15. 15.
    Marotta, E., Paradisi, C.: A Mass Spectrometry Study of Alkanes in Air Plasma at Atmospheric Pressure. J. Am. Soc. Mass Spectrom. 20, 697–707 (2009)CrossRefGoogle Scholar
  16. 16.
    Li, D.-X., Gan, L., Bronja, A., Schmitz, O.J.: Gas Chromatography Coupled to Atmospheric Pressure Ionization Mass Spectrometry (GC-API-MS): Review. Anal. Chim. Acta. 891, 43–61 (2015)CrossRefGoogle Scholar
  17. 17.
    Damas, E.Y.C., Medina, M.O.C., Clemente, A.C.N., Díaz, M.Á.D., Bravo, L.G., Ramada, R.M., Porto, R.M.d.O.: Validation of an Analytical Methodology for the Quantitative Analysis of Petroleum Hydrocarbons in Marine Sediment Samples. Química Nova. 32, 855–860 (2009)Google Scholar
  18. 18.
    Watson, J.T., Sparkman, O.D.: Introduction to Mass Spectrometry: Instrumentation, Applications, and Strategies for Data Interpretation (4th ed.). John Wiley & Sons, New Jersey (2007)Google Scholar
  19. 19.
    Bell, S.E., Ewing, R.G., Eiceman, G.A., Karpas, Z.: Atmospheric Pressure Chemical Ionization of Alkanes, Alkenes, and Cycloalkanes. J. Am. Soc. Mass Spectrom. 5, 177–185 (1994)CrossRefGoogle Scholar
  20. 20.
    Portolés, T., Pitarch, E., López, F.J., Hernández, F., Niessen, W.M.A.: Use of Soft and Hard Ionization Techniques for Elucidation of Unknown Compounds by Gas Chromatography/Time-of-Flight Mass Spectrometry. Rapid Commun. Mass Spectrom. 25, 1589–1599 (2011)CrossRefGoogle Scholar
  21. 21.
    Kind, T., Fiehn, O.: Seven Golden Rules for Heuristic Filtering of Molecular Formulas Obtained by Accurate Mass Spectrometry. BMC Bioinformatics. 8(105–105), (2007)Google Scholar

Copyright information

© American Society for Mass Spectrometry 2019

Authors and Affiliations

  1. 1.Department of ChemistryUniversity of TennesseeKnoxvilleUSA
  2. 2.Biological and Small Molecule Mass Spectrometry CoreUniversity of TennesseeKnoxvilleUSA

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