Abstract

We used a high-resolution mid-IR tunable-laser absorption spectroscopy (TLAS) system with a single IV–VI laser operating near 5.2 µm to measure the level of exhaled nitric oxide (eNO) in human breath. A method of internal calibration using simultaneous eNO and exhaled CO2 measurements eliminated the need for system calibration with gas standards. The results observed from internally calibrating the instrument for eNO measurements were compared with measurements of eNO calibrated to gas standards and were found to be similar. Various parameters of the TLAS system for eNO breath testing were examined and include gas cell pressure, exhalation time, and ambient NO concentrations. A reduction in eNO from elevated concentrations (∼44 parts in 109) to near-normal levels (<20 parts in 109) from an asthmatic patient was observed after the patient had received treatment with an inhaled glucocorticoid anti-inflammatory medication. Such measurements can help in evaluating airway inflammation and in monitoring the effectiveness of anti-inflammatory therapies.

© 2002 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. D. H. Yates, “Role of exhaled nitric oxide in asthma,” Immunol. Cell Biol. 79, 178–190 (2001).
    [CrossRef] [PubMed]
  2. K. Alving, E. Weitzberg, J. M. Lundberg, “Increased amount of nitric oxide in exhaled air of asthmatics,” Eur. Respir. J. 6, 1368–1370 (1993).
    [PubMed]
  3. S. A. Kharitonov, P. J. Barnes, “Clinical aspects of exhaled nitric oxide,” Eur. Respir. J. 16, 781–792 (2000).
    [CrossRef] [PubMed]
  4. K. J. Haley, J. M. Drazen, “Inflammation and airway function in asthma, what you see is not necessarily what you get,” Am. J. Respir. Crit. Care Med. 157, 1–3 (1998).
    [CrossRef] [PubMed]
  5. M. Bernareggi, G. Cremona, “Measurement of exhaled nitric oxide in humans and animals,” Pulmonary Pharmacol. Therapeut. 12, 331–352 (1999).
    [CrossRef]
  6. P. E. Silkoff, “Recommendations for standardized procedures for the online and offline measurement of exhaled lower respiratory nitric oxide and nasal nitric oxide in adults and children—1999,” Am. J. Respir. Crit. Care Med. 160, 2104–2117 (1999).
    [CrossRef]
  7. S. Kharitonov, K. Alving, P. J. Barnes, “Exhaled and nasal nitric oxide measurements: recommendations (ERS Task Force Report),” Eur. Respir. J. 10, 1683–1693 (1997).
    [CrossRef] [PubMed]
  8. P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
    [CrossRef] [PubMed]
  9. N. Binding, W. Muller, P. A. Czeschinski, “NO chemiluminescence in exhaled air: interference of compounds from endogenous and exogenous sources,” Eur. Respir. J. 6, 499–503 (2000).
    [CrossRef]
  10. K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–222 (1998).
    [CrossRef]
  11. M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
    [CrossRef] [PubMed]
  12. L. Konstantin, A. I. Nadezhdinskii, I. A. Adamouskaya, “Human breath trace gas content study by tunable diode laser spectroscopy technique,” Infrared Phys. Technol. 37, 181–192 (1996).
    [CrossRef]
  13. K. Namjou, P. J. McCann, W. T. Potter, “Breath testing with a Mid-IR laser spectrometer,” in Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II, A. Fried, ed., Proc. SPIE3758, 74–80 (1999).
    [CrossRef]
  14. K. R. Lewelling, P. J. McCann, “Finite element modeling predicts possibility of thermoelectrically-cooled lead-salt diode lasers,” IEEE Photon. Technol. Lett. 9, 297–299 (1997).
    [CrossRef]
  15. H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
    [CrossRef]
  16. D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
    [CrossRef]
  17. P. J. McCann, K. Namjou, X. M. Fang, “Above-room-temperature continuous wave mid-infrared photoluminescence from PbSe/PbSrSe quantum wells,” Appl. Phys. Lett. 75, 3608–3610 (1999).
    [CrossRef]
  18. X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
    [CrossRef]
  19. D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
    [CrossRef]
  20. F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
    [CrossRef]
  21. A. A. Kosterev, A. L. Malinovsky, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Cavity ringdown spectroscopic detection of nitric oxide with a continuous-wave quantum-cascade laser,” Appl. Opt. 40, 5522–5529 (2001).
    [CrossRef]
  22. L. Menzel, A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, W. Urban, “Spectroscopic detection of biological NO with a quantum cascade laser,” Appl. Phys. B. 72, 859–863 (2001).
    [CrossRef]
  23. C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
    [CrossRef]
  24. E. V. Stepanov, P. V. Zyrianov, V. A. Miliaev, “Single-breath NO detection with tunable diode lasers for pulmonary disease diagnosis,” in ALT’98 Selected Papers on Novel Laser Methods in Medicine and Biology, G. P. Koz’min, A. M. Prokhorov, V. I. Pustovoy, eds., Proc. SPIE3829, 103–109 (1999).
    [CrossRef]
  25. J. Reid, D. T. Cassidy, R. T. Menzies, “Linewidth measurements of tunable diode lasers using heterodyne and etalon techniques,” Appl. Opt. 21, 3961–3965 (1982).
    [CrossRef] [PubMed]
  26. E. D. Hinkley, C. Freed, “Direct observation of the Lorentzian line shape as limited by quantum phase noise in a laser above threshold,” Phys. Rev. Lett. 23, 277–279 (1969).
    [CrossRef]
  27. M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).
  28. A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Effective utilization of quantum-cascade distributed-feedback lasers in absorption spectroscopy,” Appl. Opt. 39, 4425–4430 (2000).
    [CrossRef]
  29. L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
    [CrossRef]
  30. A. Fried, J. R. Drummond, B. Henry, J. Fox, “Versatile integrated tunable diode laser system for precision: application for ambient measurements of OCS,” Appl. Opt. 30, 1916–1932 (1991).
    [CrossRef] [PubMed]
  31. J. J. Carr, J. M. Brown, “The human respiratory system and its measurement,” in Introduction to Biomedical Equipment Technology, 3rd ed., C. E. Stewart, ed. (Prentice-Hall, Upper Saddle River, N.J., 1998), Chap. 10.
  32. A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.
  33. R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
    [CrossRef]

2002

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
[CrossRef]

C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
[CrossRef]

2001

A. A. Kosterev, A. L. Malinovsky, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Cavity ringdown spectroscopic detection of nitric oxide with a continuous-wave quantum-cascade laser,” Appl. Opt. 40, 5522–5529 (2001).
[CrossRef]

L. Menzel, A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, W. Urban, “Spectroscopic detection of biological NO with a quantum cascade laser,” Appl. Phys. B. 72, 859–863 (2001).
[CrossRef]

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

D. H. Yates, “Role of exhaled nitric oxide in asthma,” Immunol. Cell Biol. 79, 178–190 (2001).
[CrossRef] [PubMed]

2000

S. A. Kharitonov, P. J. Barnes, “Clinical aspects of exhaled nitric oxide,” Eur. Respir. J. 16, 781–792 (2000).
[CrossRef] [PubMed]

N. Binding, W. Muller, P. A. Czeschinski, “NO chemiluminescence in exhaled air: interference of compounds from endogenous and exogenous sources,” Eur. Respir. J. 6, 499–503 (2000).
[CrossRef]

D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
[CrossRef]

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Effective utilization of quantum-cascade distributed-feedback lasers in absorption spectroscopy,” Appl. Opt. 39, 4425–4430 (2000).
[CrossRef]

1999

P. J. McCann, K. Namjou, X. M. Fang, “Above-room-temperature continuous wave mid-infrared photoluminescence from PbSe/PbSrSe quantum wells,” Appl. Phys. Lett. 75, 3608–3610 (1999).
[CrossRef]

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

M. Bernareggi, G. Cremona, “Measurement of exhaled nitric oxide in humans and animals,” Pulmonary Pharmacol. Therapeut. 12, 331–352 (1999).
[CrossRef]

P. E. Silkoff, “Recommendations for standardized procedures for the online and offline measurement of exhaled lower respiratory nitric oxide and nasal nitric oxide in adults and children—1999,” Am. J. Respir. Crit. Care Med. 160, 2104–2117 (1999).
[CrossRef]

1998

K. J. Haley, J. M. Drazen, “Inflammation and airway function in asthma, what you see is not necessarily what you get,” Am. J. Respir. Crit. Care Med. 157, 1–3 (1998).
[CrossRef] [PubMed]

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–222 (1998).
[CrossRef]

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

1997

K. R. Lewelling, P. J. McCann, “Finite element modeling predicts possibility of thermoelectrically-cooled lead-salt diode lasers,” IEEE Photon. Technol. Lett. 9, 297–299 (1997).
[CrossRef]

S. Kharitonov, K. Alving, P. J. Barnes, “Exhaled and nasal nitric oxide measurements: recommendations (ERS Task Force Report),” Eur. Respir. J. 10, 1683–1693 (1997).
[CrossRef] [PubMed]

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

1996

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

1993

K. Alving, E. Weitzberg, J. M. Lundberg, “Increased amount of nitric oxide in exhaled air of asthmatics,” Eur. Respir. J. 6, 1368–1370 (1993).
[PubMed]

1991

1982

1969

E. D. Hinkley, C. Freed, “Direct observation of the Lorentzian line shape as limited by quantum phase noise in a laser above threshold,” Phys. Rev. Lett. 23, 277–279 (1969).
[CrossRef]

Abu-Soud, H. M.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Adamouskaya, I. A.

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

Allen, T.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Alving, K.

S. Kharitonov, K. Alving, P. J. Barnes, “Exhaled and nasal nitric oxide measurements: recommendations (ERS Task Force Report),” Eur. Respir. J. 10, 1683–1693 (1997).
[CrossRef] [PubMed]

K. Alving, E. Weitzberg, J. M. Lundberg, “Increased amount of nitric oxide in exhaled air of asthmatics,” Eur. Respir. J. 6, 1368–1370 (1993).
[PubMed]

Baillargeon, J. N.

Barnes, P. J.

S. A. Kharitonov, P. J. Barnes, “Clinical aspects of exhaled nitric oxide,” Eur. Respir. J. 16, 781–792 (2000).
[CrossRef] [PubMed]

S. Kharitonov, K. Alving, P. J. Barnes, “Exhaled and nasal nitric oxide measurements: recommendations (ERS Task Force Report),” Eur. Respir. J. 10, 1683–1693 (1997).
[CrossRef] [PubMed]

Beck, M.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Bernareggi, M.

M. Bernareggi, G. Cremona, “Measurement of exhaled nitric oxide in humans and animals,” Pulmonary Pharmacol. Therapeut. 12, 331–352 (1999).
[CrossRef]

Binding, N.

N. Binding, W. Muller, P. A. Czeschinski, “NO chemiluminescence in exhaled air: interference of compounds from endogenous and exogenous sources,” Eur. Respir. J. 6, 499–503 (2000).
[CrossRef]

Brown, J. M.

J. J. Carr, J. M. Brown, “The human respiratory system and its measurement,” in Introduction to Biomedical Equipment Technology, 3rd ed., C. E. Stewart, ed. (Prentice-Hall, Upper Saddle River, N.J., 1998), Chap. 10.

Brown, L. R.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Cai, S.

Camy-Peyret, C.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Capasso, F.

Carr, J. J.

J. J. Carr, J. M. Brown, “The human respiratory system and its measurement,” in Introduction to Biomedical Equipment Technology, 3rd ed., C. E. Stewart, ed. (Prentice-Hall, Upper Saddle River, N.J., 1998), Chap. 10.

Cassidy, D. T.

Chance, K. V.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Chao, I.

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

Chapman, K. R.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Cho, A. Y.

Comhair, S. A. A.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Cremona, G.

M. Bernareggi, G. Cremona, “Measurement of exhaled nitric oxide in humans and animals,” Pulmonary Pharmacol. Therapeut. 12, 331–352 (1999).
[CrossRef]

Curl, R. F.

L. Menzel, A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, W. Urban, “Spectroscopic detection of biological NO with a quantum cascade laser,” Appl. Phys. B. 72, 859–863 (2001).
[CrossRef]

A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Effective utilization of quantum-cascade distributed-feedback lasers in absorption spectroscopy,” Appl. Opt. 39, 4425–4430 (2000).
[CrossRef]

Czeschinski, P. A.

N. Binding, W. Muller, P. A. Czeschinski, “NO chemiluminescence in exhaled air: interference of compounds from endogenous and exogenous sources,” Eur. Respir. J. 6, 499–503 (2000).
[CrossRef]

Dai, N.

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

Dana, V.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Diaz, J.

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

Drazen, J. M.

K. J. Haley, J. M. Drazen, “Inflammation and airway function in asthma, what you see is not necessarily what you get,” Am. J. Respir. Crit. Care Med. 157, 1–3 (1998).
[CrossRef] [PubMed]

Drummond, J. R.

Dweik, R. A.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Edwards, D. P.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Erzurum, S. C.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Faist, J.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–222 (1998).
[CrossRef]

Fang, X. M.

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
[CrossRef]

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

P. J. McCann, K. Namjou, X. M. Fang, “Above-room-temperature continuous wave mid-infrared photoluminescence from PbSe/PbSrSe quantum wells,” Appl. Phys. Lett. 75, 3608–3610 (1999).
[CrossRef]

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

Farver, C.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Flaud, J. M.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Fox, J.

Freed, C.

E. D. Hinkley, C. Freed, “Direct observation of the Lorentzian line shape as limited by quantum phase noise in a laser above threshold,” Phys. Rev. Lett. 23, 277–279 (1969).
[CrossRef]

Fried, A.

Furlott, H. G.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Gamache, R. R.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Gaston, B.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Gini, E.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Gmachl, C.

Goldman, A.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Grego, J.

C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
[CrossRef]

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

Haley, K. J.

K. J. Haley, J. M. Drazen, “Inflammation and airway function in asthma, what you see is not necessarily what you get,” Am. J. Respir. Crit. Care Med. 157, 1–3 (1998).
[CrossRef] [PubMed]

Hammel, J.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Henry, B.

Hinkley, E. D.

E. D. Hinkley, C. Freed, “Direct observation of the Lorentzian line shape as limited by quantum phase noise in a laser above threshold,” Phys. Rev. Lett. 23, 277–279 (1969).
[CrossRef]

Hoffstein, E.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Hofstetter, D.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Hutchinson, A. L.

Ilegems, M.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Jayasinghe, L.

F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
[CrossRef]

Jeffers, J.

C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
[CrossRef]

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

Jelen, C.

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

Jucks, K. W.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Kavuru, M.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Kharitonov, S.

S. Kharitonov, K. Alving, P. J. Barnes, “Exhaled and nasal nitric oxide measurements: recommendations (ERS Task Force Report),” Eur. Respir. J. 10, 1683–1693 (1997).
[CrossRef] [PubMed]

Kharitonov, S. A.

S. A. Kharitonov, P. J. Barnes, “Clinical aspects of exhaled nitric oxide,” Eur. Respir. J. 16, 781–792 (2000).
[CrossRef] [PubMed]

Konstantin, L.

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

Kosterev, A. A.

Lewelling, K. R.

K. R. Lewelling, P. J. McCann, “Finite element modeling predicts possibility of thermoelectrically-cooled lead-salt diode lasers,” IEEE Photon. Technol. Lett. 9, 297–299 (1997).
[CrossRef]

Lundberg, J. M.

K. Alving, E. Weitzberg, J. M. Lundberg, “Increased amount of nitric oxide in exhaled air of asthmatics,” Eur. Respir. J. 6, 1368–1370 (1993).
[PubMed]

Malinovsky, A. L.

Mandin, J. Y.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Massie, S. T.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Matlis, A.

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

McAlister, D.

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

McAlister, D. W.

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
[CrossRef]

McCann, A.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

McCann, P. J.

C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
[CrossRef]

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
[CrossRef]

P. J. McCann, K. Namjou, X. M. Fang, “Above-room-temperature continuous wave mid-infrared photoluminescence from PbSe/PbSrSe quantum wells,” Appl. Phys. Lett. 75, 3608–3610 (1999).
[CrossRef]

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

K. R. Lewelling, P. J. McCann, “Finite element modeling predicts possibility of thermoelectrically-cooled lead-salt diode lasers,” IEEE Photon. Technol. Lett. 9, 297–299 (1997).
[CrossRef]

K. Namjou, P. J. McCann, W. T. Potter, “Breath testing with a Mid-IR laser spectrometer,” in Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II, A. Fried, ed., Proc. SPIE3758, 74–80 (1999).
[CrossRef]

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

McLean, P. A.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Melchior, H.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Menzel, L.

L. Menzel, A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, W. Urban, “Spectroscopic detection of biological NO with a quantum cascade laser,” Appl. Phys. B. 72, 859–863 (2001).
[CrossRef]

Menzies, R. T.

Miliaev, V. A.

E. V. Stepanov, P. V. Zyrianov, V. A. Miliaev, “Single-breath NO detection with tunable diode lasers for pulmonary disease diagnosis,” in ALT’98 Selected Papers on Novel Laser Methods in Medicine and Biology, G. P. Koz’min, A. M. Prokhorov, V. I. Pustovoy, eds., Proc. SPIE3829, 103–109 (1999).
[CrossRef]

Mock, A.

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

Muller, W.

N. Binding, W. Muller, P. A. Czeschinski, “NO chemiluminescence in exhaled air: interference of compounds from endogenous and exogenous sources,” Eur. Respir. J. 6, 499–503 (2000).
[CrossRef]

Nadezhdinskii, A. I.

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

Namjou, K.

C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
[CrossRef]

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

P. J. McCann, K. Namjou, X. M. Fang, “Above-room-temperature continuous wave mid-infrared photoluminescence from PbSe/PbSrSe quantum wells,” Appl. Phys. Lett. 75, 3608–3610 (1999).
[CrossRef]

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–222 (1998).
[CrossRef]

K. Namjou, P. J. McCann, W. T. Potter, “Breath testing with a Mid-IR laser spectrometer,” in Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II, A. Fried, ed., Proc. SPIE3758, 74–80 (1999).
[CrossRef]

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

Nemtchinov, V.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Oesterle, U.

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Perrin, A.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Potter, W.

Potter, W. T.

K. Namjou, P. J. McCann, W. T. Potter, “Breath testing with a Mid-IR laser spectrometer,” in Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II, A. Fried, ed., Proc. SPIE3758, 74–80 (1999).
[CrossRef]

Razeghi, M.

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

Reid, J.

Rinsland, C. P.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Roller, C.

C. Roller, K. Namjou, J. Jeffers, W. Potter, P. J. McCann, J. Grego, “Simultaneous measurement of NO and CO2 in human breath using a single IV–VI mid-infrared laser,” Opt. Lett. 27, 107–109 (2002).
[CrossRef]

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

Rothman, L. S.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Rybaltowski, A.

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

Salas, R.

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

Schroeder, J.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Shi, Z.

F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
[CrossRef]

Silkoff, P. E.

P. E. Silkoff, “Recommendations for standardized procedures for the online and offline measurement of exhaled lower respiratory nitric oxide and nasal nitric oxide in adults and children—1999,” Am. J. Respir. Crit. Care Med. 160, 2104–2117 (1999).
[CrossRef]

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Sivco, D. L.

Slivken, S.

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

Slutsky, A. S.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Stepanov, E. V.

E. V. Stepanov, P. V. Zyrianov, V. A. Miliaev, “Single-breath NO detection with tunable diode lasers for pulmonary disease diagnosis,” in ALT’98 Selected Papers on Novel Laser Methods in Medicine and Biology, G. P. Koz’min, A. M. Prokhorov, V. I. Pustovoy, eds., Proc. SPIE3829, 103–109 (1999).
[CrossRef]

Szalai, J. P.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Thomassen, M. J.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Thunnissen, F. B. J. M.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Tittel, F. K.

Tor, G.

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

Urban, W.

L. Menzel, A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, W. Urban, “Spectroscopic detection of biological NO with a quantum cascade laser,” Appl. Phys. B. 72, 859–863 (2001).
[CrossRef]

Varanasi, P.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Wattson, R. B.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Weitzberg, E.

K. Alving, E. Weitzberg, J. M. Lundberg, “Increased amount of nitric oxide in exhaled air of asthmatics,” Eur. Respir. J. 6, 1368–1370 (1993).
[PubMed]

Whittaker, E. A.

Wkita, S.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Wu, H.

F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
[CrossRef]

Wu, H. Z.

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
[CrossRef]

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

Yates, D. H.

D. H. Yates, “Role of exhaled nitric oxide in asthma,” Immunol. Cell Biol. 79, 178–190 (2001).
[CrossRef] [PubMed]

Yoshino, K.

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

Zamel, N.

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

Zhao, F.

F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
[CrossRef]

Zyrianov, P. V.

E. V. Stepanov, P. V. Zyrianov, V. A. Miliaev, “Single-breath NO detection with tunable diode lasers for pulmonary disease diagnosis,” in ALT’98 Selected Papers on Novel Laser Methods in Medicine and Biology, G. P. Koz’min, A. M. Prokhorov, V. I. Pustovoy, eds., Proc. SPIE3829, 103–109 (1999).
[CrossRef]

Am. J. Respir. Crit. Care Med.

K. J. Haley, J. M. Drazen, “Inflammation and airway function in asthma, what you see is not necessarily what you get,” Am. J. Respir. Crit. Care Med. 157, 1–3 (1998).
[CrossRef] [PubMed]

P. E. Silkoff, P. A. McLean, A. S. Slutsky, H. G. Furlott, E. Hoffstein, S. Wkita, K. R. Chapman, J. P. Szalai, N. Zamel, “Marked flow-dependence of exhaled nitric oxide using a new technique to exclude nasal nitric oxide,” Am. J. Respir. Crit. Care Med. 155, 260–267 (1997).
[CrossRef] [PubMed]

P. E. Silkoff, “Recommendations for standardized procedures for the online and offline measurement of exhaled lower respiratory nitric oxide and nasal nitric oxide in adults and children—1999,” Am. J. Respir. Crit. Care Med. 160, 2104–2117 (1999).
[CrossRef]

Appl. Opt.

Appl. Phys. B.

L. Menzel, A. A. Kosterev, R. F. Curl, F. K. Tittel, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, W. Urban, “Spectroscopic detection of biological NO with a quantum cascade laser,” Appl. Phys. B. 72, 859–863 (2001).
[CrossRef]

Appl. Phys. Lett.

P. J. McCann, K. Namjou, X. M. Fang, “Above-room-temperature continuous wave mid-infrared photoluminescence from PbSe/PbSrSe quantum wells,” Appl. Phys. Lett. 75, 3608–3610 (1999).
[CrossRef]

F. Zhao, H. Wu, L. Jayasinghe, Z. Shi, “Above-room-temperature optically pumped 4.12 um midinfrared vertical-cavity surface-emitting lasers,” Appl. Phys. Lett. 80, 1129–1131 (2002).
[CrossRef]

Eur. Respir. J.

S. Kharitonov, K. Alving, P. J. Barnes, “Exhaled and nasal nitric oxide measurements: recommendations (ERS Task Force Report),” Eur. Respir. J. 10, 1683–1693 (1997).
[CrossRef] [PubMed]

N. Binding, W. Muller, P. A. Czeschinski, “NO chemiluminescence in exhaled air: interference of compounds from endogenous and exogenous sources,” Eur. Respir. J. 6, 499–503 (2000).
[CrossRef]

K. Alving, E. Weitzberg, J. M. Lundberg, “Increased amount of nitric oxide in exhaled air of asthmatics,” Eur. Respir. J. 6, 1368–1370 (1993).
[PubMed]

S. A. Kharitonov, P. J. Barnes, “Clinical aspects of exhaled nitric oxide,” Eur. Respir. J. 16, 781–792 (2000).
[CrossRef] [PubMed]

IEEE Photon. Technol. Lett.

K. R. Lewelling, P. J. McCann, “Finite element modeling predicts possibility of thermoelectrically-cooled lead-salt diode lasers,” IEEE Photon. Technol. Lett. 9, 297–299 (1997).
[CrossRef]

D. W. McAlister, P. J. McCann, H. Z. Wu, X. M. Fang, “Fabrication of thin film cleaved cavities using a bonding and cleaving fixture,” IEEE Photon. Technol. Lett. 12, 22–24 (2000).
[CrossRef]

Immunol. Cell Biol.

D. H. Yates, “Role of exhaled nitric oxide in asthma,” Immunol. Cell Biol. 79, 178–190 (2001).
[CrossRef] [PubMed]

Infrared Phys. Technol.

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

J. Appl. Phys.

D. W. McAlister, P. J. McCann, K. Namjou, H. Z. Wu, X. M. Fang, “Mid-IR photoluminescence from IV–VI layers grown on silicon,” J. Appl. Phys. 89, 3514–3516 (2001).
[CrossRef]

J. Quant. Spectrosc. Radiat. Transfer

L. S. Rothman, C. P. Rinsland, A. Goldman, S. T. Massie, D. P. Edwards, J. M. Flaud, A. Perrin, C. Camy-Peyret, V. Dana, J. Y. Mandin, J. Schroeder, A. McCann, R. R. Gamache, R. B. Wattson, K. Yoshino, K. V. Chance, K. W. Jucks, L. R. Brown, V. Nemtchinov, P. Varanasi, “The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation): 1996 edition,” J. Quant. Spectrosc. Radiat. Transfer 60, 665–710 (1998).
[CrossRef]

J. Vacuum Sci. Technol.

X. M. Fang, K. Namjou, I. Chao, P. J. McCann, N. Dai, G. Tor, “Molecular beam epitaxy of PbSrSe and PbSe/PbSrSe multiple quantum well structures for use in mid-infrared light emitting devices,” J. Vacuum Sci. Technol. 18, 1720–1723 (2000).
[CrossRef]

LEOS Newsletter

M. Razeghi, S. Slivken, A. Matlis, A. Rybaltowski, C. Jelen, J. Diaz, “Low threshold quantum cascade lasers grown by GSMBE,” LEOS Newsletter 12(6), 5–7 (1998).

Opt. Lett.

Phys. Rev. Lett.

E. D. Hinkley, C. Freed, “Direct observation of the Lorentzian line shape as limited by quantum phase noise in a laser above threshold,” Phys. Rev. Lett. 23, 277–279 (1969).
[CrossRef]

Proc. Natl. Acad. Sci.

R. A. Dweik, S. A. A. Comhair, B. Gaston, F. B. J. M. Thunnissen, C. Farver, M. J. Thomassen, M. Kavuru, J. Hammel, H. M. Abu-Soud, S. C. Erzurum, “NO chemical events in the human airway during the immediate and late antigen-induced asthmatic response,” Proc. Natl. Acad. Sci. 98(5), 2622–2627 (2001).
[CrossRef]

Pulmonary Pharmacol. Therapeut.

M. Bernareggi, G. Cremona, “Measurement of exhaled nitric oxide in humans and animals,” Pulmonary Pharmacol. Therapeut. 12, 331–352 (1999).
[CrossRef]

Science

M. Beck, D. Hofstetter, T. Allen, J. Faist, U. Oesterle, M. Ilegems, E. Gini, H. Melchior, “Continuous wave operation of a mid-infrared semiconductor laser at room-temperature,” Science 295, 301–305 (2002).
[CrossRef] [PubMed]

Thin Solid Films

H. Z. Wu, X. M. Fang, R. Salas, D. McAlister, P. J. McCann, “Transfer of PbSe/PbEuSe epilayers grown by MBE on BaF2-coated Si(111),” Thin Solid Films 352, 277–282 (1999).
[CrossRef]

Other

K. Namjou, P. J. McCann, W. T. Potter, “Breath testing with a Mid-IR laser spectrometer,” in Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II, A. Fried, ed., Proc. SPIE3758, 74–80 (1999).
[CrossRef]

J. J. Carr, J. M. Brown, “The human respiratory system and its measurement,” in Introduction to Biomedical Equipment Technology, 3rd ed., C. E. Stewart, ed. (Prentice-Hall, Upper Saddle River, N.J., 1998), Chap. 10.

A. Mock, C. Roller, K. Namjou, J. Jeffers, P. J. McCann, J. Grego, “Real-time ground level atmospheric nitric oxide measurements using a calibrated TLDAS system,” in Laser Applications to Chemical and Environmental Analysis (LACEA), Vol. 36 of OSA Trends in Optics and Photonics Series (Optical Society of America, Washington, D.C., 2002), pp. SaC4-1–SaC4-3.

E. V. Stepanov, P. V. Zyrianov, V. A. Miliaev, “Single-breath NO detection with tunable diode lasers for pulmonary disease diagnosis,” in ALT’98 Selected Papers on Novel Laser Methods in Medicine and Biology, G. P. Koz’min, A. M. Prokhorov, V. I. Pustovoy, eds., Proc. SPIE3829, 103–109 (1999).
[CrossRef]

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (15)

Fig. 1
Fig. 1

NO and CO2 line intensities in the region near 5.2 µm of the IR spectrum. Data are from the HITRAN ’96 database.28

Fig. 2
Fig. 2

Schematic of the breath-collection apparatus and the TLAS system equipped with a IV–VI mid-IR laser. The sealed cryostat under vacuum houses the IV–VI laser and the mid-IR detector. Two mass-flow controllers in a parallel configuration (not shown) maintain a constant flow of 2 L/min through the White cell.

Fig. 3
Fig. 3

Second-harmonic spectrum of exhaled alveolar-enriched breath measured at 1912.5–1913.0 cm-1. Top, the entire spectrum with a strong H2O absorption feature at 1912.55 cm-1 along with the etalon fringe (free spectral range of the etalon, 0.048 cm-1). Bottom, the absorption features of NO, CO2, and H2O are highlighted. The NO line of interest is at 1912.79 cm-1, and the CO2 line of interest is located at 1912.96 cm-1.

Fig. 4
Fig. 4

Schematic of the gas dilution system capable of producing calibrated NO concentrations of 20 ppb-10 ppm by dilution of a 10-ppm NO gas standard with purified N2. Continuous flow through the stainless-steel canister ensured steady-state homogeneous mixing of the NO and N2.

Fig. 5
Fig. 5

Gas calibration curve obtained by measuring concentrations of NO produced with the gas dilution system. The curve shows a strong linear relationship (R 2 = 0.998) between the diluted NO gas samples and the measured absorption intensities. The error bars represent the standard deviation of 200 consecutive measured NO data points for each concentration.

Fig. 6
Fig. 6

Measured second-harmonic absorption features of NO (1912.79 cm-1) for concentrations of 50, 124, 244, and 475 ppb. Each spectrum was obtained in a 4-s integration time (75 coaverages) at a cell pressure of 13 Torr.

Fig. 7
Fig. 7

Two reference spectra (Ref #1 and Ref #2) at various unknown concentrations of NO and CO2. The reference spectra are compared with measured signals over the entire absorption profiles for NO and CO2, as shown by rectangular windows.

Fig. 8
Fig. 8

Exhalation trends of eNO and eCO2 measured from an asthmatic participant and from a nonasthmatic participant over a 20-s exhalation. The asthmatic participant had end-tidal eNO absorption magnitudes (b eNO) that were 3× larger than the nonasthmatic, and both had similar end-tidal eCO2 absorption magnitudes (b eCO2 ).

Fig. 9
Fig. 9

Absorption magnitude of NO versus time for 100-ppb NO gas flowed through the cell for 20 s and for a volunteer’s breath for a 20-s exhalation. The two trends were compared with the calibrated eNO concentrations by use of Eq. (4). An absorption magnitude of b = 1 corresponds to the White cell’s being completely saturated with 100-ppb NO gas.

Fig. 10
Fig. 10

Plot of calibrated eNO breath measurements quantified with a 50-ppb NO gas standard versus eNO concentrations calculated with the eCO2 absorption magnitudes and Eq. (3). The linear relationship (R 2 = 0.939) between calibrated and calculated eNO concentrations validates the use of eCO2 as an internal calibration gas. Each point represents the mean of three consecutive measurements of eNO calculated from each volunteer, and the error bars represent the standard deviation.

Fig. 11
Fig. 11

Comparison of breath measurements at exhalation times of 5, 10, and 15 s. eNO concentrations calculated with Eq. (3) for the three exhalations were in good agreement. A 5-s exhalation time would simulate an exhalation time for a young child or an elderly or a very ill person.

Fig. 12
Fig. 12

Exhalation trends for eCO2 at various pressures from 13 Torr (1.7 kPa) to 33 Torr (4.4 kPa). At higher pressures, gas exchange rates increase, resulting in larger times required for eCO2 to escape the cell. The peak eCO2 absorption magnitudes in each trend at lower pressures decrease because there are fewer CO2 molecules occupying the White cell.

Fig. 13
Fig. 13

eNO concentrations calculated with Eq. (3) at various pressures from 13 to 40 Torr along with eNO concentration mean, μeNO, and the standard deviation, σeNO. Varying the White cell pressure did not significantly affect the measured eNO concentrations. Each point represents the mean of three consecutive measurements of calculated eNO from each volunteer, and the error bars represent the standard deviation.

Fig. 14
Fig. 14

(a) Breath eNO and eCO2 exhalation trends measured from a nonasthmatic individual at 9:00 AM when the ambient (Amb.) NO was greater than eNO. (b) eNO and eCO2 exhalation trends measured at 2:00 PM when ambient NO levels were less than eNO concentrations. Ambient NO concentrations do not significantly affect calculated eNO concentrations when Eq. (3) is used.

Fig. 15
Fig. 15

Daily measurements of eNO with Eq. (3) over a period of 10 days. The eNO concentrations from the nonasthmatic volunteer remained in the normal range from 10 to 15 ppb over the 10-day measurement period. Note the reduction in eNO concentrations for the asthmatic volunteer between day 2 and day 3 after inhaled glucocorticoid therapy was begun. A reduction in eNO confirms the anti-inflammatory action of the glucocorticoid medication.

Tables (1)

Tables Icon

Table 1 eNO Measurements of QC DFB and IV–VI Lasers

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

b= Yj Xj-N XjYj Xj2-N Xj2.
AeNOAeCO2=beNObeCO2×VNOVCO2.
CeNO=AeNOAeCO2gNOgCO2SvCO2SvNO×CeCO2.
Ccal eNO=beNObcalNO×100 ppb Reference NO.

Metrics