Phase-resolved real-time breath analysis during exercise by means of smart processing of PTR-MS data

  • Henny Schwoebel
  • Roland Schubert
  • Martin Sklorz
  • Sabine Kischkel
  • Ralf Zimmermann
  • Jochen K. Schubert
  • Wolfram Miekisch
Original Paper

Abstract

Separation of inspiratory, mixed expired and alveolar air is indispensable for reliable analysis of VOC breath biomarkers. Time resolution of direct mass spectrometers often is not sufficient to reliably resolve the phases of a breathing cycle. To realise fast on-line breath monitoring by means of direct MS utilising low-fragmentation soft ionisation, a data processing algorithm was developed to identify inspiratory and alveolar phases from MS data without any additional equipment. To test the algorithm selected breath biomarkers (acetone, isoprene, acetaldehyde and hexanal) were determined by means of quadrupole proton transfer reaction mass spectrometry (PTR-MS) in seven healthy volunteers during exercise on a stationary bicycle. The results were compared to an off-line reference method consisting of controlled alveolar breath sampling in Tedlar® bags, preconcentration by solid-phase micro extraction (SPME), separation and identification by GC-MS. Based on the data processing method, quantitative attribution of biomarkers to inspiratory, alveolar and mixed expiratory phases was possible at any time during the experiment, even under respiratory rates up to 60/min. Alveolar concentrations of the breath markers, measured by PTR-MS ranged from 130 to 2,600 ppb (acetone), 10 to 540 ppb (isoprene), 2 to 31 ppb (acetaldehyde), whereas the concentrations of hexanal were always below the limit of detection (LOD) of 3 ppb. There was good correlation between on-line PTR-MS and SPME-GC-MS measurements during phases with stable physiological parameters but results diverged during rapid changes of heart rate and minute ventilation. This clearly demonstrates the benefits of breath-resolved MS for fast on-line monitoring of exhaled VOCs.

Figure

Experimental setup showing bicycle ergometer and analytical pathways: Right side PTR-MS: identification of respiratory phases by means of the new algorithm. Left side: confirmation of PTR-MS data for exhaled isoprene by means of GC-MS analysis

Keywords

PTR-MS Data processing algorithm Stationary bicycle Breath analysis SPME-GC-MS 

References

  1. 1.
    Schubert JK, Miekisch W, Geiger K, Noedge-Schomburg GFE (2004) Breath analysis in critically ill patients: potential and limitations. Expert Rev Mol Diagn 4(5):619–629CrossRefGoogle Scholar
  2. 2.
    Schubert JK, Miekisch W, Birken T, Geiger K, Noedge-Schomburg GFE (2005) Impact of inspired substance concentrations on the results of breath analysis in mechanically ventilated patients. Biomarkers 10(2–3):138–152CrossRefGoogle Scholar
  3. 3.
    Miekisch W, Schubert JK, Noeldge-Schomburg GFE (2004) Diagnostic potential of breath analysis—focus on volatile organic compounds. Clin Chim Acta 347(1–2):25–39CrossRefGoogle Scholar
  4. 4.
    Schubert JK, Spittler KH, Braun G, Geiger K, Guttmann J (2001) CO2-controlled sampling of alveolar gas in mechanically ventilated patients. J Appl Physiol 90(2):486–492Google Scholar
  5. 5.
    Basanta M, Koimtzis T, Singh D, Wilson I, Thomas CLP (2007) An adaptive breath sampler for use with human subjects with an impaired respiratory function. Analyst 132(2):153–163CrossRefGoogle Scholar
  6. 6.
    Larstad MAE, Toren K, Bake B, Olin AC (2007) Determination of ethane, pentane and isoprene in exhaled air—effects of breath-holding, flow rate and purified air. Acta Physiol 189(1):87–98CrossRefGoogle Scholar
  7. 7.
    Lindstrom AB, Pleil JD (1996) Alveolar breath sampling and analysis to assess exposures to methyl tertiary butyl ether (MTBE) during motor vehicle refueling. J Air Waste Manag Assoc 46(7):676–682Google Scholar
  8. 8.
    Ma V, Lord H, Morley M, Pawliszyn J (2010) Application of membrane extraction with sorbent interface for breath analysis. Method mol biol 610:451–468CrossRefGoogle Scholar
  9. 9.
    Muehlberger F, Streibel T, Wieser J, Ulrich A, Zimmermann R (2005) Single photon ionization time-of-flight mass spectrometry with a pulsed electron beam pumped excimer VUV lamp for on-line gas analysis: setup and first results on cigarette smoke and human breath. Anal Chem 77(22):7408–7414CrossRefGoogle Scholar
  10. 10.
    Lindinger W, Hansel A, Jordan A (1998) On-line monitoring of volatile organic compounds at PPTV levels by means of proton-transfer-reaction mass spectrometry (PTR-MS) medical applications, food control and environmental research. Int J Mass Spectrom Ion Process 173(3):191–241CrossRefGoogle Scholar
  11. 11.
    Smith D, Španěl P (2007) The challenge of breath analysis for clinical diagnosis and therapeutic monitoring. Analyst 132(5):390–396CrossRefGoogle Scholar
  12. 12.
    Hansel A, Jordan A, Holzinger R, Prazeller P, Vogel W, Lindinger W (1995) Proton transfer reaction mass spectrometry: On-line trace gas analysis at the ppb level. Int J Mass Spectrom Ion Process 149–150:609–619CrossRefGoogle Scholar
  13. 13.
    de Gouw J, Warneke C (2007) Measurements of volatile organic compounds in the earth's atmosphere using proton-transfer-reaction mass spectrometry. Mass Spectrom Rev 26(2):223–257CrossRefGoogle Scholar
  14. 14.
    Deneris ES, Stein RA, Mead JF (1984) In vitro biosynthesis of isoprene from mevalonate utilizing a rat liver cytosolic fraction. Biochem Biophys Res Commun 123(2):691–696CrossRefGoogle Scholar
  15. 15.
    Deneris ES, Stein RA, Mead JF (1985) Acid-catalyzed formation of isoprene from a mevalonate-derived product using a rat liver cytosolic fraction. J Biol Chem 260(3):1382–1385Google Scholar
  16. 16.
    Deng C, Li N, Wang X, Zhang X, Zeng J (2005) Rapid determination of acetone in human blood by derivatization with pentafluorobenzyl hydroxylamine followed by headspace liquid-phase microextraction and chromatography/mass spectrometry. Rapid Commun Mass Spectrom 19(5):647–653CrossRefGoogle Scholar
  17. 17.
    Orhan H, van Holland B, Krab B, Moeken J, Vermeulen NPE, Hollander P, Meerman JHN (2004) Evaluation of a multi-parameter biomarker set for oxidative damage in man: Increased urinary excretion of lipid, protein and DNA oxidation products after one hour of exercise. Free Radic Res 38(12):1269–1279CrossRefGoogle Scholar
  18. 18.
    Blake RS, Monks PS, Ellis AM (2009) Proton-transfer reaction mass spectrometry. Chem Rev 109(3):861–896CrossRefGoogle Scholar
  19. 19.
    Kischkel S, Miekisch W, Sawacki A, Straker EM, Trefz P, Amann A, Schubert JK (2010) Breath biomarkers for lung cancer detection and assessment of smoking related effects—confounding variables, influence of normalization and statistical algorithms. Clin Chim Acta 411(21–22):1637–1644CrossRefGoogle Scholar
  20. 20.
    Amann A, Miekisch W, Pleil J, Risby T, Schubert W (2010) Methodological issues of sample collection and analysis of exhaled breath. In: Horvath I, de Jongste J (eds) European respiratory society monograph 49. pp 96–114Google Scholar
  21. 21.
    Birken T, Schubert J, Miekisch W, Noedge-Schomburg G (2006) A novel visually CO2 controlled alveolar breath sampling technique. Technol Health Care 14(6):499–506Google Scholar
  22. 22.
    Miekisch W, Kischkel S, Sawacki A, Liebau T, Mieth M, Schubert JK (2008) Impact of sampling procedures on the results of breath analysis. J Breath Res 2(2):026007CrossRefGoogle Scholar
  23. 23.
    King J, Kupferthaler A, Unterkofler K, Koc H, Teschl S, Teschl G, Miekisch W, Schubert J, Hinterhuber H, Amann A (2009) Isoprene and acetone concentration profiles during exercise on an ergometer. J Breath Res 3(2):027006CrossRefGoogle Scholar
  24. 24.
    Miekisch W, Hengstenberg A, Kischkel S, Beckmann U, Mieth M, Schubert JK (2010) Construction and evaluation of a versatile CO2 controlled breath collection device. Sens J IEEE 10(1):211–215CrossRefGoogle Scholar
  25. 25.
    Herbig J, Titzmann T, Beauchamp J, Kohl I, Hansel A (2008) Buffered end-tidal (BET) sampling-a novel method for real-time breath-gas analysis. J Breath Res 2(3):037008CrossRefGoogle Scholar
  26. 26.
    Herbig J, Müller M, Schallhart S, Titzmann T, Graus M, Hansel A (2009) On-line breath analysis with PTR-TOF. J Breath Res 3(2):027004CrossRefGoogle Scholar
  27. 27.
    Blake RS, Wyche KP, Ellis AM, Monks PS (2006) Chemical ionization reaction time-of-flight mass spectrometry: Multi-reagent analysis for determination of trace gas composition. Int J Mass Spectrom 254(1–2):85–93Google Scholar
  28. 28.
    Senthilmohan ST, Milligan DB, McEwan MJ, Freeman CG, Wilson PF (2000) Quantitative analysis of trace gases of breath during exercise using the new SIFT-MS technique. Redox Report 5(2–3):151–153CrossRefGoogle Scholar
  29. 29.
    Karl T, Prazeller P, Mayr D, Jordan A, Rieder J, Fall R, Lindinger W (2001) Human breath isoprene and its relation to blood cholesterol levels: new measurements and modeling. J Appl Physiol 91(2):762–770Google Scholar
  30. 30.
    Filser J, Csanady G, Denk B, Hartmann M, Kauffmann A, Kassler W, Kreuzer P, Puetz C, Shen J, Stei P (1996) Toxicokinetics of isoprene in rodents and humans. Toxicology 113(1–3):278–287CrossRefGoogle Scholar
  31. 31.
    King J, Koc H, Unterkofler K, Mochalski P, Kupferthaler A, Teschl G, Teschl S, Hinterhuber H, Amann A (2010) Physiological modeling of isoprene dynamics in exhaled breath. J Theor Biol 267(4):626–637CrossRefGoogle Scholar
  32. 32.
    Deng C, Zhang J, Yu X, Zhang W, Zhang X (2004) Determination of acetone in human breath by gas chromatography-mass spectrometry and solid-phase microextraction with on-fiber derivatization. J Chromatogr B 810(2):269–275Google Scholar
  33. 33.
    Beauchamp J, Herbig J, Gutmann R, Hansel A (2008) On the use of Tedlar® bags for breath-gas sampling and analysis. J Breath Res 2(4):046001CrossRefGoogle Scholar
  34. 34.
    Pet'ka J, Etievant P, Callement G (2000) Suitability of different plastic materials for head or nose spaces short term storage. Analusis 28(4):330–335CrossRefGoogle Scholar
  35. 35.
    McGarvey LJ, Shorten CV (2000) The effects of adsorption on the reusability of Tedlar; air sampling bags. Am Ind Hyg Assoc J 61(3):375–380Google Scholar
  36. 36.
    Steeghs MML, Cristescu SM, Harren FJM (2007) The suitability of Tedlar bags for breath sampling in medical diagnostic research. Physiol Meas 28(1):73–84CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Henny Schwoebel
    • 1
    • 2
    • 3
  • Roland Schubert
    • 1
  • Martin Sklorz
    • 2
    • 3
  • Sabine Kischkel
    • 1
  • Ralf Zimmermann
    • 2
    • 3
  • Jochen K. Schubert
    • 1
  • Wolfram Miekisch
    • 1
  1. 1.Department of Anaesthesia and Intensive Care MedicineUniversity of RostockRostockGermany
  2. 2.Joint Mass Spectrometry Centre, Chair of Analytical ChemistryUniversity of RostockRostockGermany
  3. 3.Cooperation Group Analysis of Complex Molecular Systems, Helmholtz Zentrum MuenchenGerman Research Center for Environmental HealthNeuherbergGermany

Personalised recommendations