The fluorescence from a turbid medium such as biologic tissue contains information about scattering and absorption, as well as the intrinsic fluorescence, i.e., the fluorescence from an optically thin sample of pure fluorophores. The interplay of scattering and absorption can result in severe distortion of the intrinsic spectral features. These distortions can be removed by use of a photon-migration-based picture and information from simultaneously acquired fluorescence and reflectance spectra. We present experimental evidence demonstrating the validity of such an approach for extracting the intrinsic fluorescence for a wide range of scatterer and absorber concentrations in tissue models, <i>ex vivo</i> and <i>in vivo</i> tissues. We show that variations in line shape and intensity in intrinsic tissue fluorescence are significantly reduced compared with the corresponding measured fluorescence.
© 2001 Optical Society of America
(170.5280) Medical optics and biotechnology : Photon migration
(170.7050) Medical optics and biotechnology : Turbid media
(290.4210) Scattering : Multiple scattering
(300.1030) Spectroscopy : Absorption
(300.2530) Spectroscopy : Fluorescence, laser-induced
Markus G. Müller, Irene Georgakoudi, Qingguo Zhang, Jun Wu, and Michael S. Feld, "Intrinsic fluorescence spectroscopy in turbid media: disentangling effects of scattering and absorption," Appl. Opt. 40, 4633-4646 (2001)