Abstract

We describe a high-resolution real-time spectroscopy system targeted to ethane gas with sensitivity ≥70 ppt and response time from ≥0.7 s. The measurement technique is based on a mid-IR lead-salt laser passing through a Herriott cell through which a gas sample flows. We compare wavelength scanning and locked configurations and discuss their relative merits. The technology has been motivated by clinical breath testing applications, ethane being widely regarded as the most important breath biomarker for cell damage via free-radical-mediated oxidative attack. We discuss preliminary human and animal studies in which ultrasensitive real-time ethane detection offers new diagnostic and monitoring potential.

© 2005 Optical Society of America

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  1. P. Španěl, D. Smith, “Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath,” Med. Biol. Eng. Comput. 34, 409–419 (1996).
    [CrossRef] [PubMed]
  2. K. L. Moskalenko, A. I. Nadezhdinskii, I. A. Adamovskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
    [CrossRef]
  3. G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
    [PubMed]
  4. R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
    [CrossRef] [PubMed]
  5. C. A. Riely, G. Cohen, M. Lieberman, “Ethane evolution: a new index of lipid peroxidation,” Science, 183, 208–210 (1974).
    [CrossRef] [PubMed]
  6. C. R. Wade, A. M. van Rij, “In-vivo lipid peroxidation in man as measured by the respiratory excretion of ethane, pentane and other low-molecular-weight hydrocarbons,” Anal. Biochem. 150, 1–7 (1985).
    [CrossRef] [PubMed]
  7. C. M. F. Kneepkens, G. Lepage, C. C. Roy, “The potential of the hydrocarbon breath test as a measure of lipid peroxidation,” Free Radic. Biol. Med. 17, 127–160 (1994).
    [CrossRef] [PubMed]
  8. M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
    [CrossRef] [PubMed]
  9. A. Manolis, “The diagnostic potential of breath analysis,” Clin. Chem. 29, 5–15 (1983).
    [PubMed]
  10. P. Paredi, S. A. Kharitonov, P. J. Barnes, “Analysis of expired air for oxidation products,” Am. J. Respir. Crit. Care Med. 166, S31–S37 (2002).
    [CrossRef] [PubMed]
  11. M. Phillips, J. Greenberg, J. Awad, “Metabolic and environmental origins of volatile organic compounds in breath,” J. Clin. Pathol. 47, 1052–1053 (1994).
    [CrossRef] [PubMed]
  12. M. S. Daugherty, T. M. Ludden, R. F. Burk, “Metabolism of ethane and pentane to carbon dioxide by the rat,” Drug Metab. Dispos. 16, 666–671 (1988).
    [PubMed]
  13. B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
    [CrossRef]
  14. F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
    [CrossRef]
  15. M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
    [CrossRef]
  16. H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
    [CrossRef]
  17. G. von Basum, D. Halmer, P. Hering, M. Mürtz, “Parts per trillion sensitivity for ethane in air with an optical parametric oscillator cavity leak-out spectrometer,” Opt. Lett. 29, 797–799 (2004).
    [CrossRef] [PubMed]
  18. D. R. Herriott, H. Kogelnik, R. Kompfner, “Off-axis paths in spherical mirror resonators,” Appl. Opt. 3, 523–526 (1964).
    [CrossRef]
  19. J. M. Supplee, E. A. Whittaker, W. Lenth, “Theoretical description of frequency modulation and wavelength modulation spectroscopy,” Appl. Opt. 33, 6294–6302 (1994).
    [CrossRef] [PubMed]
  20. G. Gibson, S. D. Monk, M. Padgett, “A field-portable, laser-diode spectrometer for the ultra-sensitive detection of hydrocarbon gases,” J. Mod. Opt. 49, 769–776 (2002).
    [CrossRef]
  21. M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
    [CrossRef] [PubMed]
  22. E. Aghdassi, J. P. Allard, “Breath alkanes as a marker of oxidative stress in different clinical conditions,” Free Radic. Biol. Med. 28, 880–886 (2000).
    [CrossRef] [PubMed]
  23. S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
    [CrossRef] [PubMed]
  24. V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
    [CrossRef] [PubMed]
  25. N. E. Robinson, “International workshop on equine chronic airway disease,” Equine Vet. J. 33, 5–19 (2001).
    [CrossRef] [PubMed]
  26. S. A. Kharitonov, P. J. Barnes, “Exhaled nitric oxide, carbon monoxide and breath condensate in inflammatory lung disease and response to medical treatment,” in Disease Markers in Exhaled Breath, C. Lenfant, ed. (Marcel Dekker, New York, 2003), Chap. 14.
  27. N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).
  28. C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

2004 (2)

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

G. von Basum, D. Halmer, P. Hering, M. Mürtz, “Parts per trillion sensitivity for ethane in air with an optical parametric oscillator cavity leak-out spectrometer,” Opt. Lett. 29, 797–799 (2004).
[CrossRef] [PubMed]

2003 (1)

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

2002 (3)

P. Paredi, S. A. Kharitonov, P. J. Barnes, “Analysis of expired air for oxidation products,” Am. J. Respir. Crit. Care Med. 166, S31–S37 (2002).
[CrossRef] [PubMed]

M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
[CrossRef]

G. Gibson, S. D. Monk, M. Padgett, “A field-portable, laser-diode spectrometer for the ultra-sensitive detection of hydrocarbon gases,” J. Mod. Opt. 49, 769–776 (2002).
[CrossRef]

2001 (2)

H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
[CrossRef]

N. E. Robinson, “International workshop on equine chronic airway disease,” Equine Vet. J. 33, 5–19 (2001).
[CrossRef] [PubMed]

2000 (1)

E. Aghdassi, J. P. Allard, “Breath alkanes as a marker of oxidative stress in different clinical conditions,” Free Radic. Biol. Med. 28, 880–886 (2000).
[CrossRef] [PubMed]

1999 (3)

N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

1998 (1)

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

1996 (2)

P. Španěl, D. Smith, “Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath,” Med. Biol. Eng. Comput. 34, 409–419 (1996).
[CrossRef] [PubMed]

K. L. Moskalenko, A. I. Nadezhdinskii, I. A. Adamovskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
[CrossRef]

1994 (3)

M. Phillips, J. Greenberg, J. Awad, “Metabolic and environmental origins of volatile organic compounds in breath,” J. Clin. Pathol. 47, 1052–1053 (1994).
[CrossRef] [PubMed]

J. M. Supplee, E. A. Whittaker, W. Lenth, “Theoretical description of frequency modulation and wavelength modulation spectroscopy,” Appl. Opt. 33, 6294–6302 (1994).
[CrossRef] [PubMed]

C. M. F. Kneepkens, G. Lepage, C. C. Roy, “The potential of the hydrocarbon breath test as a measure of lipid peroxidation,” Free Radic. Biol. Med. 17, 127–160 (1994).
[CrossRef] [PubMed]

1991 (1)

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

1990 (1)

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

1988 (1)

M. S. Daugherty, T. M. Ludden, R. F. Burk, “Metabolism of ethane and pentane to carbon dioxide by the rat,” Drug Metab. Dispos. 16, 666–671 (1988).
[PubMed]

1985 (1)

C. R. Wade, A. M. van Rij, “In-vivo lipid peroxidation in man as measured by the respiratory excretion of ethane, pentane and other low-molecular-weight hydrocarbons,” Anal. Biochem. 150, 1–7 (1985).
[CrossRef] [PubMed]

1983 (1)

A. Manolis, “The diagnostic potential of breath analysis,” Clin. Chem. 29, 5–15 (1983).
[PubMed]

1974 (1)

C. A. Riely, G. Cohen, M. Lieberman, “Ethane evolution: a new index of lipid peroxidation,” Science, 183, 208–210 (1974).
[CrossRef] [PubMed]

1972 (1)

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

1964 (1)

Adamovskaya, I. A.

K. L. Moskalenko, A. I. Nadezhdinskii, I. A. Adamovskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
[CrossRef]

Aghdassi, E.

E. Aghdassi, J. P. Allard, “Breath alkanes as a marker of oxidative stress in different clinical conditions,” Free Radic. Biol. Med. 28, 880–886 (2000).
[CrossRef] [PubMed]

Allard, J. P.

E. Aghdassi, J. P. Allard, “Breath alkanes as a marker of oxidative stress in different clinical conditions,” Free Radic. Biol. Med. 28, 880–886 (2000).
[CrossRef] [PubMed]

Angeletti, C. A.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Archibald, I.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Art, T.

N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).

Awad, J.

M. Phillips, J. Greenberg, J. Awad, “Metabolic and environmental origins of volatile organic compounds in breath,” J. Clin. Pathol. 47, 1052–1053 (1994).
[CrossRef] [PubMed]

Barnes, P. J.

P. Paredi, S. A. Kharitonov, P. J. Barnes, “Analysis of expired air for oxidation products,” Am. J. Respir. Crit. Care Med. 166, S31–S37 (2002).
[CrossRef] [PubMed]

S. A. Kharitonov, P. J. Barnes, “Exhaled nitric oxide, carbon monoxide and breath condensate in inflammatory lung disease and response to medical treatment,” in Disease Markers in Exhaled Breath, C. Lenfant, ed. (Marcel Dekker, New York, 2003), Chap. 14.

Bartsch, H.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Bisson, S. E.

M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
[CrossRef]

Bracher, V.

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

Burk, R. F.

M. S. Daugherty, T. M. Ludden, R. F. Burk, “Metabolism of ethane and pentane to carbon dioxide by the rat,” Drug Metab. Dispos. 16, 666–671 (1988).
[PubMed]

Camus, B. S.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Cary, P.

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

Christley, R. M.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Cohen, G.

C. A. Riely, G. Cohen, M. Lieberman, “Ethane evolution: a new index of lipid peroxidation,” Science, 183, 208–210 (1974).
[CrossRef] [PubMed]

Cooper, J. C.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Courtial, J.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Cummin, D. R. S.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Dahnke, H.

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
[CrossRef]

Daugherty, M. S.

M. S. Daugherty, T. M. Ludden, R. F. Burk, “Metabolism of ethane and pentane to carbon dioxide by the rat,” Drug Metab. Dispos. 16, 666–671 (1988).
[PubMed]

Gibson, G.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

G. Gibson, S. D. Monk, M. Padgett, “A field-portable, laser-diode spectrometer for the ultra-sensitive detection of hydrocarbon gases,” J. Mod. Opt. 49, 769–776 (2002).
[CrossRef]

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Gillespie, S.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Giuntini, C.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Greenberg, J.

M. Phillips, J. Greenberg, J. Awad, “Metabolic and environmental origins of volatile organic compounds in breath,” J. Clin. Pathol. 47, 1052–1053 (1994).
[CrossRef] [PubMed]

Gruenig, G.

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

Halmer, D.

G. von Basum, D. Halmer, P. Hering, M. Mürtz, “Parts per trillion sensitivity for ethane in air with an optical parametric oscillator cavity leak-out spectrometer,” Opt. Lett. 29, 797–799 (2004).
[CrossRef] [PubMed]

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

Harren, F. J. M.

M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
[CrossRef]

Hecker, A.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

Hering, P.

G. von Basum, D. Halmer, P. Hering, M. Mürtz, “Parts per trillion sensitivity for ethane in air with an optical parametric oscillator cavity leak-out spectrometer,” Opt. Lett. 29, 797–799 (2004).
[CrossRef] [PubMed]

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
[CrossRef]

Hermann, M.

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

Herriott, D. R.

Hietanen, E.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Hirst, B.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Hotchkiss, J. W.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Kharitonov, S. A.

P. Paredi, S. A. Kharitonov, P. J. Barnes, “Analysis of expired air for oxidation products,” Am. J. Respir. Crit. Care Med. 166, S31–S37 (2002).
[CrossRef] [PubMed]

S. A. Kharitonov, P. J. Barnes, “Exhaled nitric oxide, carbon monoxide and breath condensate in inflammatory lung disease and response to medical treatment,” in Disease Markers in Exhaled Breath, C. Lenfant, ed. (Marcel Dekker, New York, 2003), Chap. 14.

Kirschvink, N.

N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).

Kleine, D.

H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
[CrossRef]

Kneepkens, C. M. F.

C. M. F. Kneepkens, G. Lepage, C. C. Roy, “The potential of the hydrocarbon breath test as a measure of lipid peroxidation,” Free Radic. Biol. Med. 17, 127–160 (1994).
[CrossRef] [PubMed]

Knutson, M. D.

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

Kogelnik, H.

Kompfner, R.

Kraehenmann, A.

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

Kühnemann, F.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

Lekeux, P.

N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).

Lenth, W.

Lepage, G.

C. M. F. Kneepkens, G. Lepage, C. C. Roy, “The potential of the hydrocarbon breath test as a measure of lipid peroxidation,” Free Radic. Biol. Med. 17, 127–160 (1994).
[CrossRef] [PubMed]

Li, S.

M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
[CrossRef]

Lieberman, M.

C. A. Riely, G. Cohen, M. Lieberman, “Ethane evolution: a new index of lipid peroxidation,” Science, 183, 208–210 (1974).
[CrossRef] [PubMed]

Lim, A. K.

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

Love, S.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Ludden, T. M.

M. S. Daugherty, T. M. Ludden, R. F. Burk, “Metabolism of ethane and pentane to carbon dioxide by the rat,” Drug Metab. Dispos. 16, 666–671 (1988).
[PubMed]

Manolis, A.

A. Manolis, “The diagnostic potential of breath analysis,” Clin. Chem. 29, 5–15 (1983).
[PubMed]

Martis, A. A. E.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

Mlynek, J.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

Mon, T. R.

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

Monk, S.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Monk, S. D.

G. Gibson, S. D. Monk, M. Padgett, “A field-portable, laser-diode spectrometer for the ultra-sensitive detection of hydrocarbon gases,” J. Mod. Opt. 49, 769–776 (2002).
[CrossRef]

Moskalenko, K. L.

K. L. Moskalenko, A. I. Nadezhdinskii, I. A. Adamovskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
[CrossRef]

Mürtz, M.

G. von Basum, D. Halmer, P. Hering, M. Mürtz, “Parts per trillion sensitivity for ethane in air with an optical parametric oscillator cavity leak-out spectrometer,” Opt. Lett. 29, 797–799 (2004).
[CrossRef] [PubMed]

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
[CrossRef]

Mussi, A.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Nadezhdinskii, A. I.

K. L. Moskalenko, A. I. Nadezhdinskii, I. A. Adamovskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
[CrossRef]

Padgett, M.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

G. Gibson, S. D. Monk, M. Padgett, “A field-portable, laser-diode spectrometer for the ultra-sensitive detection of hydrocarbon gases,” J. Mod. Opt. 49, 769–776 (2002).
[CrossRef]

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Paredi, P.

P. Paredi, S. A. Kharitonov, P. J. Barnes, “Analysis of expired air for oxidation products,” Am. J. Respir. Crit. Care Med. 166, S31–S37 (2002).
[CrossRef] [PubMed]

Pauling, L.

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

Petruzzelli, S.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Phillips, M.

M. Phillips, J. Greenberg, J. Awad, “Metabolic and environmental origins of volatile organic compounds in breath,” J. Clin. Pathol. 47, 1052–1053 (1994).
[CrossRef] [PubMed]

Podlaha, O.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Preston, T.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Riely, C. A.

C. A. Riely, G. Cohen, M. Lieberman, “Ethane evolution: a new index of lipid peroxidation,” Science, 183, 208–210 (1974).
[CrossRef] [PubMed]

Robinson, A. B.

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

Robinson, N. E.

N. E. Robinson, “International workshop on equine chronic airway disease,” Equine Vet. J. 33, 5–19 (2001).
[CrossRef] [PubMed]

Roy, C. C.

C. M. F. Kneepkens, G. Lepage, C. C. Roy, “The potential of the hydrocarbon breath test as a measure of lipid peroxidation,” Free Radic. Biol. Med. 17, 127–160 (1994).
[CrossRef] [PubMed]

Saracci, R.

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Schiller, S.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

Schneider, K.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

Skeldon, K.

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Smith, D.

P. Španěl, D. Smith, “Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath,” Med. Biol. Eng. Comput. 34, 409–419 (1996).
[CrossRef] [PubMed]

Smith, N.

N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).

Španel, P.

P. Španěl, D. Smith, “Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath,” Med. Biol. Eng. Comput. 34, 409–419 (1996).
[CrossRef] [PubMed]

Supplee, J. M.

Teranishi, R.

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

Urban, W.

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

van Herpen, M. M. J. W.

M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
[CrossRef]

van Rij, A. M.

C. R. Wade, A. M. van Rij, “In-vivo lipid peroxidation in man as measured by the respiratory excretion of ethane, pentane and other low-molecular-weight hydrocarbons,” Anal. Biochem. 150, 1–7 (1985).
[CrossRef] [PubMed]

Viteri, F. E.

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

von Basum, G.

G. von Basum, D. Halmer, P. Hering, M. Mürtz, “Parts per trillion sensitivity for ethane in air with an optical parametric oscillator cavity leak-out spectrometer,” Opt. Lett. 29, 797–799 (2004).
[CrossRef] [PubMed]

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

von Fellenberg, V. R.

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

Wade, C. R.

C. R. Wade, A. M. van Rij, “In-vivo lipid peroxidation in man as measured by the respiratory excretion of ethane, pentane and other low-molecular-weight hydrocarbons,” Anal. Biochem. 150, 1–7 (1985).
[CrossRef] [PubMed]

Whittaker, E. A.

Winder, R. C. N.

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

Wyse, C. A.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Yam, P. S.

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

Am. J. Respir. Crit. Care Med. (1)

P. Paredi, S. A. Kharitonov, P. J. Barnes, “Analysis of expired air for oxidation products,” Am. J. Respir. Crit. Care Med. 166, S31–S37 (2002).
[CrossRef] [PubMed]

Anal. Biochem. (1)

C. R. Wade, A. M. van Rij, “In-vivo lipid peroxidation in man as measured by the respiratory excretion of ethane, pentane and other low-molecular-weight hydrocarbons,” Anal. Biochem. 150, 1–7 (1985).
[CrossRef] [PubMed]

Anal. Chem. (1)

R. Teranishi, T. R. Mon, A. B. Robinson, P. Cary, L. Pauling, “Gas chromatography of volatiles from breath and urine,” Anal. Chem. 44, 18–20 (1972).
[CrossRef] [PubMed]

Appl. Opt. (2)

Appl. Phys. B. (2)

F. Kühnemann, K. Schneider, A. Hecker, A. A. E. Martis, W. Urban, S. Schiller, J. Mlynek, “Photoacoustic trace-gas detection using a cw single-frequency parameteric oscillator,” Appl. Phys. B. 66, 741–745 (1998).
[CrossRef]

H. Dahnke, D. Kleine, P. Hering, M. Mürtz, “Real-time monitoring of ethane in human breath using mid-infrared cavity leak out spectroscopy,” Appl. Phys. B. 72, 971–975, (2001).
[CrossRef]

Appl. Phys. Lett. (1)

M. M. J. W. van Herpen, S. Li, S. E. Bisson, F. J. M. Harren, “Photoacoustic trace gas detection of ethane using a continuously tunable continuous-wave optical parameteric oscillator based on periodically poled lithium niobate,” Appl. Phys. Lett. 81, 1157–1159 (2002).
[CrossRef]

Chest (1)

S. Petruzzelli, E. Hietanen, H. Bartsch, B. S. Camus, A. Mussi, C. A. Angeletti, R. Saracci, C. Giuntini, “Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients,” Chest 98, 930–935 (1990).
[CrossRef] [PubMed]

Clin. Chem. (1)

A. Manolis, “The diagnostic potential of breath analysis,” Clin. Chem. 29, 5–15 (1983).
[PubMed]

Drug Metab. Dispos. (1)

M. S. Daugherty, T. M. Ludden, R. F. Burk, “Metabolism of ethane and pentane to carbon dioxide by the rat,” Drug Metab. Dispos. 16, 666–671 (1988).
[PubMed]

Equine Vet. J. (2)

V. Bracher, V. R. von Fellenberg, R. C. N. Winder, G. Gruenig, M. Hermann, A. Kraehenmann, “An investigation of the incidence of chronic obstructive pulmonary disease (COPD) in random populations of Swiss horses,” Equine Vet. J. 23, 136–141 (1991).
[CrossRef] [PubMed]

N. E. Robinson, “International workshop on equine chronic airway disease,” Equine Vet. J. 33, 5–19 (2001).
[CrossRef] [PubMed]

Equine Vet. J. Suppl. (1)

N. Kirschvink, T. Art, N. Smith, P. Lekeux, “Effect of exercise and COPD crisis on isoprostane concentration in plasma and bronchoalveolar lavage fluid in horses,” Equine Vet. J. Suppl. 30, 88–91 (1999).

Free Radic. Biol. Med. (4)

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

E. Aghdassi, J. P. Allard, “Breath alkanes as a marker of oxidative stress in different clinical conditions,” Free Radic. Biol. Med. 28, 880–886 (2000).
[CrossRef] [PubMed]

C. M. F. Kneepkens, G. Lepage, C. C. Roy, “The potential of the hydrocarbon breath test as a measure of lipid peroxidation,” Free Radic. Biol. Med. 17, 127–160 (1994).
[CrossRef] [PubMed]

M. D. Knutson, A. K. Lim, F. E. Viteri, “A practical and reliable method for measuring ethane and pentane in expired air from humans,” Free Radic. Biol. Med. 27, 560–571 (1999).
[CrossRef] [PubMed]

Geophys. Res. Lett. (1)

B. Hirst, G. Gibson, S. Gillespie, I. Archibald, O. Podlaha, K. Skeldon, J. Courtial, S. Monk, M. Padgett, “Oil and gas prospecting by ultra-sensitive optical gas detection with inverse gas dispersion modelling,” Geophys. Res. Lett. 31, L12115 (2004).
[CrossRef]

Infrared Phys. Technol. (1)

K. L. Moskalenko, A. I. Nadezhdinskii, I. A. Adamovskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
[CrossRef]

J. Appl. Physiol. (1)

G. von Basum, H. Dahnke, D. Halmer, P. Hering, M. Mürtz, “Online recording of ethane traces in human breath via infrared laser spectroscopy,” J. Appl. Physiol. 95, 2583–2590 (2003).
[PubMed]

J. Clin. Pathol. (1)

M. Phillips, J. Greenberg, J. Awad, “Metabolic and environmental origins of volatile organic compounds in breath,” J. Clin. Pathol. 47, 1052–1053 (1994).
[CrossRef] [PubMed]

J. Mod. Opt. (1)

G. Gibson, S. D. Monk, M. Padgett, “A field-portable, laser-diode spectrometer for the ultra-sensitive detection of hydrocarbon gases,” J. Mod. Opt. 49, 769–776 (2002).
[CrossRef]

Med. Biol. Eng. Comput. (1)

P. Španěl, D. Smith, “Selected ion flow tube: a technique for quantitative trace gas analysis of air and breath,” Med. Biol. Eng. Comput. 34, 409–419 (1996).
[CrossRef] [PubMed]

Opt. Lett. (1)

Science (1)

C. A. Riely, G. Cohen, M. Lieberman, “Ethane evolution: a new index of lipid peroxidation,” Science, 183, 208–210 (1974).
[CrossRef] [PubMed]

Other (2)

C. A. Wyse, K. Skeldon, J. W. Hotchkiss, G. Gibson, P. S. Yam, R. M. Christley, T. Preston, D. R. S. Cummin, M. Padgett, J. C. Cooper, S. Love, “The effect of environmental modification on exhaled ethane, carbon monoxide and hydrogen peroxide in horses with respiratory inflammation,” Vet. Rec. (in press).

S. A. Kharitonov, P. J. Barnes, “Exhaled nitric oxide, carbon monoxide and breath condensate in inflammatory lung disease and response to medical treatment,” in Disease Markers in Exhaled Breath, C. Lenfant, ed. (Marcel Dekker, New York, 2003), Chap. 14.

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Figures (12)

Fig. 1
Fig. 1

Experimental configuration for the TDLS system. In the topology shown the laser is modulated at 8 kHz (freq B) and subsequent demodulation of the reference and sample signals at twice this frequency provide the output. A much slower sawtooth waveform (freq A) is superposed on the laser to ramp it back and forth through the ethane transition.

Fig. 2
Fig. 2

Simplified schematic of the system emphasizing the changes made to produce a line-locked version of the instrument. To the left, typical traces of the signals at various key points are indicated. An additional phase-sensitive detector (PSD3) is employed to demodulate the reference cell signal at the modulation frequency f. The output of PSD3 offers a bipolar control signal that forces the laser to track the ethane transition.

Fig. 3
Fig. 3

Comparative indication of some life-science and environmental studies we have undertaken in which the trade-off between measurement accuracy and response time has been adjusted to suit the application. The terms ‘rs’ and ‘os’ refer to remote sampling (i.e., bag collection) and to online sampling (direct instrument access), respectively.

Fig. 4
Fig. 4

Agreement between a sequence of empirically calculated ethane concentrations together with the measured values with the scanning configuration (left graph) and the line-locked configuration (right graph). The ethane samples were mixed from a calibrated source with 5% basic concentration tolerance.

Fig. 5
Fig. 5

Comparison of the performance of the line-locked and the scanning configuration. The line-locked configuration is treated as a sample and hold mode, whereby a scan period of t corresponds to a Nyquist frequency of 1/2t.

Fig. 6
Fig. 6

Traces showing nitrogen testing for the line-locked instrument for two extremes of PSD1 time constant 30 ms and 1 s. The upper curves compare the standard deviation measured over a 60-s interval, and the lower traces show the response of the instrument to an ethane sample.

Fig. 7
Fig. 7

Response of the TDLS system (as defined by the sample rise from 10% to 90% of the plateau value) plotted against the time constant of PSD1. The intersect with the y axis (equivalent to having no electronic low-pass filtering) gives the fastest response possible given the fluid dynamics of the system.

Fig. 8
Fig. 8

Two tests of the servo action. (a) Drift associated with the first part of the trace is characteristic of thermal variation of the laser, but this is considerably suppressed when the servo is closed. (b) Servo response as measured at the 2f demodulation point of PSD1 is shown as the servo is switched off, followed by a step change being made to the laser temperature. The singularities exhibited relate to the division by zeros in the calibration process when the transition drifts through nulls. The servo can be seen to track the instrument back to the center of the transition (provided the demodulated signal at f is still within its bipolar region).

Fig. 9
Fig. 9

Screen dump from the controlling software showing the instrument measurement from a prepared sample bag containing a mixture of ethane and methane. In our experience, such a high level of methane is unusual from human subjects but can be more common in animals, as was particularly notable in our equine study.

Fig. 10
Fig. 10

Typical plot of the spread of breath ethane for a healthy subject over 8 days of sample collection.

Fig. 11
Fig. 11

Example of a trace recorded by the TDLS system from a patient with COPD using a multi-impedance bag system (inset picture). The trace shows the alveolar rise that could be important in assessing patient condition.

Fig. 12
Fig. 12

Effect of airway inflammation on clinical scores and exhaled ethane. The plot is essentially a chart recording of the TDLS system output. The leftmost peaks beneath the horizontal bar shows a breath sample from a horse with airway inflammation being opened up to the system. The rightmost peaks beneath the horizontal bar shows a breath sample from the same animal after therapeutic intervention to reduce inflammation. This is a typical result from a 6-horse study and illustrates significant correlation between clinical scores of inflammation (shown by the black bars) and of breath ethane.

Tables (1)

Tables Icon

Table 1 Measured Ethane Concentration and Standard Deviation of Room Air over a 60-s Sampling Period for the Line-Locked Instrument

Metrics