Alternative reagents for chemical noise reduction in liquid chromatography-mass spectrometry using selective ion-molecule reactions

  • Xinghua GuoEmail author
  • Andries P. Bruins
  • Thomas R. Covey
  • Martin Trötzmüller
  • Ernst Lankmayr


Reduction of ionic chemical background noise based on selective gas-phase reactions with chosen neutral reagents has been proven to be a very promising approach in liquid chromatography—mass spectrometry (LC-MS). In this study further investigations on alternative reagents including the disulfides (dimethyl disulfide, diethyl disulfide, methyl propyl disulfide), dimethyl trisulfide, ethylene oxide, and butadiene monoxide, for example, have been carried out. Tandem mass spectrometric studies of ion/molecule reactions indicate that—besides dimethyl disulfide—ethylene oxide and butadiene monoxide also exhibit very efficient reactions with background ions. Furthermore, it is confirmed that the reactions are very selective according to the test with some analyte ions. In contrast to its rapid reactions with background ions, ethylene oxide does not react, or reacts much less, with these analytes. Therefore, it can be used as an alternative reagent for noise reduction. Although reactions of the other tested neutral reagents with background ions are evaluated, they are generally not suitable as reagents for this purpose because of lack of reactivity or dramatic ion losses during reactions.


Ethylene Oxide Ethylene Oxide DMDS Dimethyl Disulfide Trisulfide 
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  1. 1.
    Yamashita, M.; Fenn, J. B. Electrospray Ion Source: Another Variation on the Free-Jet Theme. J. Phys. Chem. 1984, 88, 4451–4459.CrossRefGoogle Scholar
  2. 2.
    Covey, T. R.; Lee, E. D.; Bruins, A. P.; Henion, J. D. Liquid-Chromatography Mass-Spectrometry. Anal. Chem. 1986, 58, 1451.CrossRefGoogle Scholar
  3. 3.
    Busch, K. L. Chemical Noise in Mass Spectrometry. Spectroscopy. 2002, 17, 32–36.Google Scholar
  4. 4.
    Guo, X.; Bruins, A. P.; Covey, T. R. Characterization of Typical Chemical Background Interferences in Atmospheric Pressure Ionization Liquid Chromatography-Mass Spectrometry. Rapid Commun. Mass Spectrom. 2006, 20, 3145–3150.CrossRefGoogle Scholar
  5. 5.
    Marquet, P. Is LC-MS Suitable for a Comprehensive Screening of Drugs and Poisons in Clinical Toxicology?. Ther. Drug Monit. 2002, 24, 125–133.CrossRefGoogle Scholar
  6. 6.
    Alavi, A.; Cousins, L. M.; Javahery, G.; Jolliffe, C.; Vuckovic, D. Proceedings of the 52nd ASMS Conference on Mass Spectrometry; MPH-127, Nashville, TN; 2004.Google Scholar
  7. 7.
    Product brochure: API 5000™ LC-MS/MS System, Publication No. 114BR15-02. Applied Biosystems/MDS Sciex: Concord, Canada; April 2006.Google Scholar
  8. 8.
    Purves, R. W.; Guevremont, R. Mass Spectrometric Characterization of a High-Field Asymmetric Waveform Ion Mobility Spectrometer. Rev. Sci. Instrum. 1998, 69, 4094–4105.CrossRefGoogle Scholar
  9. 9.
    Guevremont, R.; Purves, R. W. Apparatus and Method for Desolvating and Focusing Ions for Introduction into a Mass Spectrometer. U. S. Patent 6 504 149, 2003.Google Scholar
  10. 10.
    Windig, W.; Phalp, J. M.; Payne, A. W. A Noise and Background Reduction Method for Component Detection in Liquid Chromatography/Mass Spectrometry. Anal. Chem. 1996, 68, 3602–3606.CrossRefGoogle Scholar
  11. 11.
    Andreev, V. P.; Rejtar, T.; Chen, H.-S.; Moskovets, E. V.; Ivanov, A. R.; Karger, B. L. A Universal Denoising and Peak Picking Algorithm for LC-MS Based on Matched Filtration in the Chromatographic Time Domain. Anal. Chem. 2003, 75, 6314–6326.CrossRefGoogle Scholar
  12. 12.
    Muddiman, D. C.; Rockwood, A. L.; Gao, Q.; Severs, J. C.; Udseth, H. R.; Smith, R. D.; Proctor, A. Application of Sequential Paired Covariance to Capillary Electrophoresis Electrospray Ionization Time-of-Flight Mass Spectrometry: Unraveling the Signal from the Noise in the Electropherogram. Anal. Chem. 1995, 67, 4371–4375.CrossRefGoogle Scholar
  13. 13.
    Visentini, J.; Kwong, E. C.; Carrier, A.; Zidarov, D.; Bertrand, M. J. Comparison of Softwares Used for the Detection of Analytes Present at Low Levels in Liquid Chromatographic—Mass Spectrometric Experiments. J. Chromatogr. A. 1995, 712, 31–43.CrossRefGoogle Scholar
  14. 14.
    Le Blanc, Y., Bloomfield, N. Real-Time Dynamic Background Subtraction: Improving the Automated Ion Selection Process, Technical Note 114TN02-01. Applied Biosystems/MDS Sciex: Concord, Canada.Google Scholar
  15. 15.
    Ramsey, R. S.; Goeringer, D. E.; McLuckey, S. A. Active-Chemical Background-Noise Reduction in Capillary Electrophoresis/Ion Trap Mass-Spectrometry. Anal. Chem. 1993, 65, 3521–3524.CrossRefGoogle Scholar
  16. 16.
    Fleming, C. M.; Kowalswi, B. R.; Apffel, A.; Hancock, W. S. Windowed Mass Selection Method: A New Data Processing Algorithm for Liquid Chromatography—Mass Spectrometry Data. J. Chromatogr. A. 1999, 849, 71–85.CrossRefGoogle Scholar
  17. 17.
    Guo, X.; Bruins, A. P.; Covey T. R. Chemical Noise Reduction for Mass Spectrometry. PCT International Patent WO 2007/092873 A2, 2007.Google Scholar
  18. 18.
    Guo, X.; Bruins, A. P.; Covey, T. R. Method to Reduce Chemical Background Interference in Atmospheric Pressure Ionization Liquid Chromatography—Mass Spectrometry Using Exclusive Reactions with the Chemical Reagent Dimethyl Disulfide. Anal. Chem. 2007, 79, 4013–4021.CrossRefGoogle Scholar
  19. 19.
    Tanner, S. D.; Baranov, V. I. Bandpass Reactive Collision Cell. U. S. Patent 6 140 638, 2000.Google Scholar
  20. 20.
    Jarvis, M. J. Y.; Koyanagi, G. K.; Zhao, X.; Bohme, D. K. Scrubbing Ions with Molecules: Kinetic Studies of Chemical Noise Reduction in Mass Spectrometry Using Ion-Molecule Reactions with Dimethyl Disulfide. Anal. Chem. 2007, 79, 4006–4012.CrossRefGoogle Scholar
  21. 21.
    Chait, B. T.; Krutchinsky, A. N. Method and Apparatus for Improved Signal-to-Noise Ratio in Mass Spectrometry. U. S. Patent 6 610 976, 2003.Google Scholar
  22. 22.
    Douglas, D. J.; French, J. B. Collisional Focusing Effects in Radio Frequency Quadrupoles. J. Am. Soc. Mass Spectrom. 1992, 3, 398–408.CrossRefGoogle Scholar
  23. 23.
    Watkins, M. A.; WeWora, D. V.; Winger, B. E.; Kenttämaa, H. I. Compound Screening for the Presence of the Primary N-Oxide Functionality via Ion-Molecule Reactions in a Mass Spectrometer. Anal. Chem. 2005, 77, 5311–5316.CrossRefGoogle Scholar
  24. 24.
    Moraes, L. A. B.; Eberlin, M. N. The Gas-Phase Meerwein Reaction. Chem. Eur. J. 2000, 6, 897–905.CrossRefGoogle Scholar
  25. 25.
    Cooks, R. G.; Chen, H.; Eberlin, M. N.; Zheng, X.; Tao, W. A. Polar Acetalization and Transacetalization in the Gas Phase: The Eberlin Reaction. Chem. Rev. 2006, 106, 188–211.CrossRefGoogle Scholar
  26. 26.
    Hager, J. Method for Improving Signal-to-Noise Ratios for Atmospheric Pressure Ionization Mass Spectrometry. U. S. Patent 6 700 120, 2004.Google Scholar
  27. 27. Scholar

Copyright information

© American Society for Mass Spectrometry 2009

Authors and Affiliations

  • Xinghua Guo
    • 1
    Email author
  • Andries P. Bruins
    • 2
  • Thomas R. Covey
    • 3
  • Martin Trötzmüller
    • 1
  • Ernst Lankmayr
    • 1
  1. 1.Institute of Analytical Chemistry and RadiochemistryGraz University of TechnologyGraz, SteiermarkAustria
  2. 2.Mass Spectrometry Core FacilityUniversity of GroningenGroningenThe Netherlands
  3. 3.Applied Biosystems/MDS SciexConcordCanada

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