skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Improved molecular level identification of organic compounds using comprehensive two-dimensional chromatography, dual ionization energies and high resolution mass spectrometry

Abstract

A new analytical methodology combining comprehensive two-dimensional gas chromatography (GC×GC), dual ionization energies and high resolution time of flight mass spectrometry has been developed that improves molecular level identification of organic compounds in complex environmental samples. GC×GC maximizes compound separation providing cleaner mass spectra by minimizing erroneous fragments from interferences and co-eluting peaks. Traditional electron ionization (EI, 70 eV) provides MS fragmentation patterns that can be matched to published EI MS libraries while vacuum ultraviolet photoionization (VUV, 10.5 eV) yields MS with reduced fragmentation enhancing the abundance of the molecular ion providing molecular formulas when combined with high resolution mass spectrometry. We demonstrate this new approach by applying it to a sample of organic aerosol. In this sample, 238 peaks were matched to EI MS library data with FM ≥ 800 but a fifth (42 compounds) were determined to be incorrectly identified because the molecular formula was not confirmed by the VUV MS data. This highlights the importance of using a complementary technique to confirm compound identifications even for peaks with very good matching statistics. In total, 171 compounds were identified by EI MS matching to library spectra with confirmation of the molecular formula from the high resolution VUV MSmore » data and were not dependent on the matching statistics being above a threshold value. A large number of unidentified peaks were still observed with FM < 800, which in routine analysis would typically be neglected. Where possible, these peaks were assigned molecular formulas from the VUV MS data (211 in total). In total, the combination of EI and VUV MS data provides more than twice as much molecular level peak information than traditional approaches and improves confidence in the identification of individual organic compounds. The molecular formula data from the VUV MS data was used, in conjunction with GC×GC retention times and the observed EI MS, to generate a new, searchable EI MS library compatible with the standard NIST MS search program. This library is deliberately dynamic and editable so that other end users can add new entries and update existing entries as new information becomes available.A new analytical methodology has been developed to improve molecular level identification of organic compounds in complex samples.« less

Authors:
ORCiD logo [1];  [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]
  1. Univ. of California, Berkeley, CA (United States). Dept. of Environmental Sciences Policy and Management
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  3. Univ. of California, Berkeley, CA (United States). Dept. of Environmental Sciences Policy and Management; Univ. of California, Berkeley, CA (United States). Dept. of Civil and Environmental Engineering
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Chemical Sciences, Geosciences & Biosciences Division; National Science Foundation (NSF)
OSTI Identifier:
1456975
Grant/Contract Number:  
AC02-05CH11231; 0922562
Resource Type:
Accepted Manuscript
Journal Name:
Analyst
Additional Journal Information:
Journal Volume: 142; Journal Issue: 13; Journal ID: ISSN 0003-2654
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; 54 ENVIRONMENTAL SCIENCES; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Worton, David R., Decker, Monika, Isaacman-VanWertz, Gabriel, Chan, Arthur W. H., Wilson, Kevin R., and Goldstein, Allen H. Improved molecular level identification of organic compounds using comprehensive two-dimensional chromatography, dual ionization energies and high resolution mass spectrometry. United States: N. p., 2017. Web. doi:10.1039/c7an00625j.
Worton, David R., Decker, Monika, Isaacman-VanWertz, Gabriel, Chan, Arthur W. H., Wilson, Kevin R., & Goldstein, Allen H. Improved molecular level identification of organic compounds using comprehensive two-dimensional chromatography, dual ionization energies and high resolution mass spectrometry. United States. doi:10.1039/c7an00625j.
Worton, David R., Decker, Monika, Isaacman-VanWertz, Gabriel, Chan, Arthur W. H., Wilson, Kevin R., and Goldstein, Allen H. Mon . "Improved molecular level identification of organic compounds using comprehensive two-dimensional chromatography, dual ionization energies and high resolution mass spectrometry". United States. doi:10.1039/c7an00625j. https://www.osti.gov/servlets/purl/1456975.
@article{osti_1456975,
title = {Improved molecular level identification of organic compounds using comprehensive two-dimensional chromatography, dual ionization energies and high resolution mass spectrometry},
author = {Worton, David R. and Decker, Monika and Isaacman-VanWertz, Gabriel and Chan, Arthur W. H. and Wilson, Kevin R. and Goldstein, Allen H.},
abstractNote = {A new analytical methodology combining comprehensive two-dimensional gas chromatography (GC×GC), dual ionization energies and high resolution time of flight mass spectrometry has been developed that improves molecular level identification of organic compounds in complex environmental samples. GC×GC maximizes compound separation providing cleaner mass spectra by minimizing erroneous fragments from interferences and co-eluting peaks. Traditional electron ionization (EI, 70 eV) provides MS fragmentation patterns that can be matched to published EI MS libraries while vacuum ultraviolet photoionization (VUV, 10.5 eV) yields MS with reduced fragmentation enhancing the abundance of the molecular ion providing molecular formulas when combined with high resolution mass spectrometry. We demonstrate this new approach by applying it to a sample of organic aerosol. In this sample, 238 peaks were matched to EI MS library data with FM ≥ 800 but a fifth (42 compounds) were determined to be incorrectly identified because the molecular formula was not confirmed by the VUV MS data. This highlights the importance of using a complementary technique to confirm compound identifications even for peaks with very good matching statistics. In total, 171 compounds were identified by EI MS matching to library spectra with confirmation of the molecular formula from the high resolution VUV MS data and were not dependent on the matching statistics being above a threshold value. A large number of unidentified peaks were still observed with FM < 800, which in routine analysis would typically be neglected. Where possible, these peaks were assigned molecular formulas from the VUV MS data (211 in total). In total, the combination of EI and VUV MS data provides more than twice as much molecular level peak information than traditional approaches and improves confidence in the identification of individual organic compounds. The molecular formula data from the VUV MS data was used, in conjunction with GC×GC retention times and the observed EI MS, to generate a new, searchable EI MS library compatible with the standard NIST MS search program. This library is deliberately dynamic and editable so that other end users can add new entries and update existing entries as new information becomes available.A new analytical methodology has been developed to improve molecular level identification of organic compounds in complex samples.},
doi = {10.1039/c7an00625j},
journal = {Analyst},
number = 13,
volume = 142,
place = {United States},
year = {2017},
month = {5}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 7 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

A review of current applications of mass spectrometry for biomarker/molecular tracer elucidations
journal, January 2005

  • Simoneit, Bernd R. T.
  • Mass Spectrometry Reviews, Vol. 24, Issue 5
  • DOI: 10.1002/mas.20036

Oil Weathering after the Deepwater Horizon Disaster Led to the Formation of Oxygenated Residues
journal, August 2012

  • Aeppli, Christoph; Carmichael, Catherine A.; Nelson, Robert K.
  • Environmental Science & Technology, Vol. 46, Issue 16
  • DOI: 10.1021/es3015138

Heterogeneous OH Oxidation of Motor Oil Particles Causes Selective Depletion of Branched and Less Cyclic Hydrocarbons
journal, September 2012

  • Isaacman, Gabriel; Chan, Arthur W. H.; Nah, Theodora
  • Environmental Science & Technology, Vol. 46, Issue 19
  • DOI: 10.1021/es302768a

A Mass Scale Based on CH 2 = 14.0000 for High Resolution Mass Spectrometry of Organic Compounds.
journal, December 1963


Estimating probabilities of correct identification from results of mass spectral library searches
journal, April 1994


Origins and composition of fine atmospheric carbonaceous aerosol in the Sierra Nevada Mountains, California
journal, January 2011

  • Worton, D. R.; Goldstein, A. H.; Farmer, D. K.
  • Atmospheric Chemistry and Physics, Vol. 11, Issue 19
  • DOI: 10.5194/acp-11-10219-2011

Observational Insights into Aerosol Formation from Isoprene
journal, September 2013

  • Worton, David R.; Surratt, Jason D.; LaFranchi, Brian W.
  • Environmental Science & Technology, Vol. 47, Issue 20
  • DOI: 10.1021/es4011064

Known and Unexplored Organic Constituents in the Earth's Atmosphere
journal, March 2007

  • Goldstein, Allen H.; Galbally, Ian E.
  • Environmental Science & Technology, Vol. 41, Issue 5
  • DOI: 10.1021/es072476p

The Influence of Molecular Structure and Aerosol Phase on the Heterogeneous Oxidation of Normal and Branched Alkanes by OH
journal, May 2013

  • Ruehl, Christopher R.; Nah, Theodora; Isaacman, Gabriel
  • The Journal of Physical Chemistry A, Vol. 117, Issue 19
  • DOI: 10.1021/jp401888q

Improved Resolution of Hydrocarbon Structures and Constitutional Isomers in Complex Mixtures Using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry
journal, February 2012

  • Isaacman, Gabriel; Wilson, Kevin R.; Chan, Arthur W. H.
  • Analytical Chemistry, Vol. 84, Issue 5
  • DOI: 10.1021/ac2030464

Field-Deployable, High-Resolution, Time-of-Flight Aerosol Mass Spectrometer
journal, December 2006

  • DeCarlo, Peter F.; Kimmel, Joel R.; Trimborn, Achim
  • Analytical Chemistry, Vol. 78, Issue 24
  • DOI: 10.1021/ac061249n

OH-Initiated Heterogeneous Oxidation of Cholestane: A Model System for Understanding the Photochemical Aging of Cyclic Alkane Aerosols
journal, November 2013

  • Zhang, Haofei; Ruehl, Christopher R.; Chan, Arthur W. H.
  • The Journal of Physical Chemistry A, Vol. 117, Issue 47
  • DOI: 10.1021/jp407994m

Thermal desorption comprehensive two-dimensional gas chromatography for in-situ measurements of organic aerosols
journal, April 2008

  • Goldstein, Allen H.; Worton, David R.; Williams, Brent J.
  • Journal of Chromatography A, Vol. 1186, Issue 1-2
  • DOI: 10.1016/j.chroma.2007.09.094

Search criteria and rules for comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry analysis of airborne particulate matter
journal, November 2003


Light and Molecular Ions: The Emergence of Vacuum UV Single-Photon Ionization in MS
journal, June 2009

  • Hanley, Luke; Zimmermann, Ralf
  • Analytical Chemistry, Vol. 81, Issue 11
  • DOI: 10.1021/ac8013675

Thermal Desorption Comprehensive Two-Dimensional Gas Chromatography: An Improved Instrument for In-Situ Speciated Measurements of Organic Aerosols
journal, April 2012

  • Worton, David R.; Kreisberg, Nathan M.; Isaacman, Gabriel
  • Aerosol Science and Technology, Vol. 46, Issue 4
  • DOI: 10.1080/02786826.2011.634452

Comprehensive multidimensional separation methods by hyphenation of single-photon ionization time-of-flight mass spectrometry (SPI-TOF-MS) with GC and GC×GC
journal, July 2010

  • Eschner, Markus S.; Welthagen, Werner; Gröger, Thomas M.
  • Analytical and Bioanalytical Chemistry, Vol. 398, Issue 3
  • DOI: 10.1007/s00216-010-4021-0

Using Comprehensive Two-Dimensional Gas Chromatography to Study the Atmosphere
journal, April 2010


Comprehensive Chemical Characterization of Hydrocarbons in NIST Standard Reference Material 2779 Gulf of Mexico Crude Oil
journal, October 2015

  • Worton, David R.; Zhang, Haofei; Isaacman-VanWertz, Gabriel
  • Environmental Science & Technology, Vol. 49, Issue 22
  • DOI: 10.1021/acs.est.5b03472

Optimization and testing of mass spectral library search algorithms for compound identification
journal, September 1994

  • Stein, Stephen E.; Scott, Donald R.
  • Journal of the American Society for Mass Spectrometry, Vol. 5, Issue 9
  • DOI: 10.1016/1044-0305(94)87009-8

Source apportionment of airborne particulate matter using organic compounds as tracers
journal, November 1996


Bioremediation approaches for organic pollutants: A critical perspective
journal, November 2011

  • Megharaj, Mallavarapu; Ramakrishnan, Balasubramanian; Venkateswarlu, Kadiyala
  • Environment International, Vol. 37, Issue 8
  • DOI: 10.1016/j.envint.2011.06.003

Understanding evolution of product composition and volatility distribution through in-situ GC × GC analysis: a case study of longifolene ozonolysis
journal, January 2011

  • Isaacman, G.; Worton, D. R.; Kreisberg, N. M.
  • Atmospheric Chemistry and Physics, Vol. 11, Issue 11
  • DOI: 10.5194/acp-11-5335-2011

Comprehensive Two-Dimensional Gas Chromatography using an On-Column Thermal Modulator Interface
journal, June 1991


Major components of atmospheric organic aerosol in southern California as determined by hourly measurements of source marker compounds
journal, January 2010

  • Williams, B. J.; Goldstein, A. H.; Kreisberg, N. M.
  • Atmospheric Chemistry and Physics, Vol. 10, Issue 23
  • DOI: 10.5194/acp-10-11577-2010

Performance of the vacuum ultraviolet high-resolution and high-flux beamline for chemical dynamics studies at the Advanced Light Source
journal, May 1997

  • Heimann, P. A.; Koike, M.; Hsu, C. W.
  • Review of Scientific Instruments, Vol. 68, Issue 5
  • DOI: 10.1063/1.1148082