Turbidity-free fluorescence spectroscopy of biological tissue

We present a method based on photon migration of extracting intrinsic fluor escence spectra from turbid media, using concomitantly measured fluorescenc e and reflectance. Intrinsic fluorescence is defined as fluorescence that i s due only to fluorophores, without interference from the absorbers and sca tterers that are present. Application to fluorescence spectra taken with ti ssue phantoms and human mucosal tissues demonstrates excellent agreement in both spectral line shape and intensity between the extracted and the direc tly measured intrinsic fluorescence spectra. (C) 2000 Optical Society of Am erica.