Аннотация:Many researchers during past 20 years have used the laser fluorescence spectroscopy (LFS) for in vivo tissue diagnosis.
But in the up-to-date medical in vivo LFS there is a problem of quantification of the fluorophores concentrations in
optically-turbid biotissues basing on measurements of the laser induced fluorescence on a surface of the tissues. The
purpose of our work is both experimental and theoretical study of the character of dependences of measured fluorescence
intensities on tissues’ optical properties and on fluorophores concentrations in tissues. In the experimental part of our
study the measurements of the superficial fluorescence on phantoms at different known concentration of fluorophores in
them were carried out. As a result experimental dependences of the registered intensities of the laser induced
fluorescence emission on fluorophores concentration were plotted. In the theoretical part of our study the analytical
solution for a fluorescence emission by Kokhanovsky’s method based on the well-known two-flux Kubelka-Munk
approach (KMA) was used. Besides, in the study the Kokhanovsky’s method was modified by its association with our
improved KMA, allowing us to receive exact solutions for boundary intensities collected by an optical probe. As a result
a set of theoretical curves describing the influence of fluorophore concentration in tissues on the registered intensities
was obtained as well. Both experimental and theoretical results show a good qualitative agreement between each other.
Also these results show that the dependence of the fluorescence intensity from tissues’ optical properties and from the
concentration of fluorophores can be both nonlinear and non-monotonic.