A theoretical approach to the spectrophotometry of nucleic acids on paper disks.

A linear approximated model is presented that takes into account a local anisotropic distribution of scattered light within a turbid medium. Light intensity depends upon the distance from the boundary surface of the scattering centers, so that the probability of photon-chromophore interaction is a function of the distance. For the sake of simplicity it is assumed that there are only two main zones, corresponding to two probabilities of photon-chromophore interaction. In this form, the Kubelka-Munk theory fits the experimental data supplied by bichromatic photometry of nucleic acids on paper disks.