Applied Physics B

, Volume 90, Issue 2, pp 345–354 | Cite as

VCSEL-based oxygen spectroscopy for structural analysis of pharmaceutical solids

  • T. Svensson
  • M. Andersson
  • L. Rippe
  • S. Svanberg
  • S. Andersson-Engels
  • J. Johansson
  • S. Folestad
Article

Abstract

We present a minimalistic and flexible single-beam instrumentation based on sensitive tunable diode laser absorption spectroscopy (TDLAS) and its use in structural analysis of highly scattering pharmaceutical solids. By utilising a vertical cavity surface emitting laser (VCSEL) for sensing of molecular oxygen dispersed in tablets, we address structural properties such as porosity. Experiments involve working with unknown path lengths, severe backscattering and diffuse light. These unusual experimental conditions has led to the use of the term gas in scattering media absorption spectroscopy (GASMAS). By employing fully digital wavelength modulation spectroscopy and coherent sampling, system sensitivity in ambient air experiments reaches the 10-7 range. Oxygen absorption exhibited by our tablets, being influenced by both sample porosity and scattering, was in the range 8×10-5 to 2×10-3, and corresponds to 2–50 mm of path length through ambient air (Leq). The day-to-day reproducibility was on average 1.8% (0.3 mm Leq), being limited by mechanical positioning. This is the first time sub-millimetre sensitivity is reached in GASMAS. We also demonstrate measurements on gas transport on a 1-s time scale. By employing pulsed illumination and time-correlated single-photon counting, we reveal that GASMAS exhibits excellent correlation with time-domain photon migration. In addition, we introduce an optical measure of porosity by relating oxygen absorption to average photon time-of-flight. Finally, the simplicity, robustness and low cost of this novel TDLAS instrumentation provide industrial potential.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, S. Svanberg, Opt. Lett. 26, 16 (2001)CrossRefADSGoogle Scholar
  2. 2.
    G. Somesfalean, M. Sjöholm, J. Alnis, C. af Klinteberg, S. Andersson-Engels, S. Svanberg, Appl. Opt. 41, 3538 (2002)CrossRefADSGoogle Scholar
  3. 3.
    J. Alnis, B. Anderson, M. Sjöholm, G. Somesfalean, S. Svanberg, Appl. Phys. B 77, 691 (2003)CrossRefADSGoogle Scholar
  4. 4.
    M. Andersson, L. Persson, M. Sjöholm, S. Svanberg, Opt. Express 14, 3641 (2006)CrossRefADSGoogle Scholar
  5. 5.
    L. Persson, H. Gao, M. Sjöholm, S. Svanberg, Opt. Lasers Eng. 44, 687 (2006)CrossRefGoogle Scholar
  6. 6.
    L. Persson, K. Svanberg, S. Svanberg, Appl. Phys. B 82, 313 (2006)CrossRefADSGoogle Scholar
  7. 7.
    M. Andersson, L. Persson, T. Svensson, S. Svanberg, Rev. Sci. Instrum. 78, 113107 (2007)CrossRefADSGoogle Scholar
  8. 8.
    L. Persson, M. Andersson, M. Cassel-Engquist, K. Svanberg, S. Svanberg, J. Biomed. Opt. 12, 054001 (2007)CrossRefADSGoogle Scholar
  9. 9.
    J.A. Silver, Appl. Opt. 31, 707 (1992)ADSCrossRefGoogle Scholar
  10. 10.
    T. Fernholz, H. Teichert, V. Ebert, Appl. Phys. B 75, 229 (2002)CrossRefADSGoogle Scholar
  11. 11.
    Maxim, Appl. Note 1040 (2002)Google Scholar
  12. 12.
    I. Linnerud, P. Kaspersen, T. Jaeger, Appl. Phys. B 67, 297 (1998)CrossRefADSGoogle Scholar
  13. 13.
    M.G. Allen, Meas. Sci. Technol. 9, 545 (1998)CrossRefADSGoogle Scholar
  14. 14.
    E. Schlosser, J. Wolfrum, L. Hildebrandt, H. Seifert, B. Oser, V. Ebert, Appl. Phys. B 75, 237 (2002)CrossRefADSGoogle Scholar
  15. 15.
    G.B. Rieker, H. Li, X. Liu, J.B. Jeffries, R.K. Hanson, M.G. Allen, S.D. Wehe, P.A. Mulhall, H.S. Kindle, Meas. Sci. Technol. 18, 1195 (2007)CrossRefADSGoogle Scholar
  16. 16.
    J. Johansson, S. Folestad, S. Svanberg, M. Sjöholm, G. Somesfalean, C. Abrahamsson, S. Andersson-Engels, Int. Patent No. PCT WO 03/078983 (2003)Google Scholar
  17. 17.
    T. Svensson, L. Persson, M. Andersson, S. Svanberg, S. Andersson-Engels, J. Johansson, S. Folestad, Appl. Spectrosc. 61, 784 (2007)CrossRefADSGoogle Scholar
  18. 18.
    T. Svensson, M. Andersson, L. Rippe, J. Johansson, S. Folestad, S. Andersson-Engels, Opt. Lett. 33, 80 (2008)Google Scholar
  19. 19.
    D.S. Bomse, A.C. Stanton, J.A. Silver, Appl. Opt. 31, 718 (1992)ADSGoogle Scholar
  20. 20.
    P. Kluczynski, J. Gustafsson, Å. Lindberg, O. Axner, Spectrochim. Acta B 56, 1277 (2001)CrossRefADSGoogle Scholar
  21. 21.
    L.S. Rothman, D. Jacquemart, A. Barbe, D. Chris Benner, M. Birk, L.R. Brown, M.R. Carleer, C. Chackerian Jr., K. Chance, L.H. Coudert, V. Dana, V.M. Devi, J.-M. Flaud, R.R. Gamache, A. Goldman, J.-M. Hartmann, K.W. Jucks, A.G. Maki, J.-Y. Mandin, S.T. Massie, J. Orphal, A. Perrin, C.P. Rinsland, M.A.H. Smith, J. Tennyson, R.N. Tolchenov, R.A. Toth, J. Vander Auwera, P. Varanasi, G. Wagner, J. Quant. Spectrosc. Radiat. Transf. 96, 139 (2005)CrossRefADSGoogle Scholar
  22. 22.
    H.P. Zappe, M. Hess, M. Moser, R. Hovel, K. Gulden, H.P. Gauggel, F.M. di Sopra, Appl. Opt. 39, 2475 (2000)ADSGoogle Scholar
  23. 23.
    P. Vogel, V. Ebert, Appl. Phys. B 72, 127 (2001)ADSGoogle Scholar
  24. 24.
    L. Bergström, S. Stemme, T. Dahlfors, H. Arwin, L. Ödberg, Cellulose 6, 1 (1999)CrossRefGoogle Scholar
  25. 25.
    C. Sun, J. Pharm. Sci. 94, 2132 (2005)Google Scholar
  26. 26.
    B.W. Pogue, M.S. Patterson, J. Biomed. Opt. 11, 041102 (2006)CrossRefADSGoogle Scholar
  27. 27.
    J. Johansson, S. Folestad, M. Josefson, A. Sparen, C. Abrahamsson, S. Andersson-Engels, S. Svanberg, Appl. Spectrosc. 56, 725 (2002)CrossRefADSGoogle Scholar
  28. 28.
    T. Svensson, M. Einarsdóttír, K. Svanberg, S. Andersson-Engels, J. Biomed. Opt. 12, 014022 (2007)CrossRefADSGoogle Scholar
  29. 29.
    D. Contini, F. Martelli, G. Zaccanti, Appl. Opt. 36, 4587 (1997)ADSGoogle Scholar
  30. 30.
    F. Martelli, D. Contini, A. Taddeucci, G. Zaccanti, Appl. Opt. 36, 4600 (1997)ADSGoogle Scholar
  31. 31.
    P. Werle, R. Miicke, F. Slemr, Appl. Phys. B 57, 131 (1993)CrossRefADSGoogle Scholar
  32. 32.
    R. Arndt, J. Appl. Phys. 36, 2522 (1965)CrossRefADSGoogle Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • T. Svensson
    • 1
  • M. Andersson
    • 1
  • L. Rippe
    • 1
  • S. Svanberg
    • 1
  • S. Andersson-Engels
    • 1
  • J. Johansson
    • 2
  • S. Folestad
    • 2
  1. 1.Department of PhysicsLund UniversityLundSweden
  2. 2.Astra Zeneca R&DMölndalSweden

Personalised recommendations