Changes in optical properties of human whole blood in vitro due to slow heating

Research output: Contribution to journalArticle

Abstract

Optical properties of human whole blood were investigated in vitro at 633 nm using a double integrating sphere set-up, The blood flow was maintained at a constant rate through a flow cell while continuously heating the blood at 0.2-1.1 degrees C/min from approximately 25 to 55 degrees C in a heat exchanger, A small, but rather abrupt decrease in the scattering asymmetry factor (g-factor) of 1.7 +/- 0.6% and a similar increase in the scattering coefficient of 2.9 +/- 0.6% were observed at approximately 45-46 degrees C yielding an increase in the reduced scattering coefficient of 40 +/- 10%. Furthermore, a continuous, manifest increase in the absorption coefficient was seen with increasing temperature, on average 80 +/- 70% from 25 to 50 degrees C. The effect of the heating on the blood cells was also studied under a white-light transmission microscope, A sudden change in the shape of the red blood cells, from disc-shaped to spherical, was observed at approximately the same temperature at which the distinct changes in g-factor and scattering coefficient were observed, i.e. at 45-46 degrees C, The results indicate that this shape transformation could explain the sudden change in scattering properties.

Details

Authors
  • A. M. K. Nilsson
  • G. W. Lucassen
  • W. Verkruysse
  • M. J. C. van Gemert
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics
Original languageEnglish
Pages (from-to)366-373
JournalPhotochemistry and Photobiology
Volume65
Issue number2
Publication statusPublished - 1997
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes

Related research output

Enejder, A. M. K., 1997, Department of Physics, Lund University. 279 p.

Research output: ThesisDoctoral Thesis (compilation)

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