IN-VIVO FLUORESCENCE SPECTROSCOPY OF HUMA N SKIN - PRINCIPLES AND APPLICATION TO PENETRATION MEASUREMENTS

The fluorescence properties of untreated human skin and the penetratio n of topically applied drugs were measured in vivo using a commerciall y available fluorescence spectrometer which was adapted to in vivo-mea surements on skin by means of optical fibres and a remote viewing head . The intensity and characteristics of the intrinsic fluorescences of human skin and their dependences upon several parameters like pigmenta tion, water content of the skin or depth of the horny layer are shown. The principles of the penetration measurements based on the fluoresce nce of the skin or the fluorescence of the drug topically applied to t he skin are described and measurements of the penetration of some drug s are reported.