Photoacoustic spectroscopy applied to the study of protoporphyrin IX induced in mice

We used Photoacoustic Spectroscopy (PAS) to study protoporphyrin DC (PpIX) in mice skin induced from delta -aminolevulinic acid (ALA) administrated by intraperitoneal route to CD 1 female mice. From obtained PAS spectra and b y using the Phase-Resolved Method We estimated that PpIX in skin was prefer entially concentrated near to the inner side of the basal membrane. It was also obtained the total attenuation coefficient (mu (t)) of the mouse skin as a function of wavelength. The obtained mu (t) values, in particular at 6 30 nm agree with the literature values for similar samples. Also it was est imated in a first approximation the degradation time of PpIX when is irradi ated at its maximum optical absorption wavelength.