A STUDY OF THE PHOTOSENSITIZING PROPERTIES OF MESOTETRAPHENYLPORPHYRIN

Juarranz, A.; Cañete, M.; Villanueva, A.; Dominguez, V. and Stockert, J.C. Dpt. Biología, Universidad Autónoma de Madrid. Spain.  

INTRODUCTION

            One of the basic objectives of our research lines is the characterization of new and more efficient photosensitizers, that show both, minimal dark toxicity and secondary effects, as well as high photodynamic yield using red light irradiation (Juarranz et al., 1995; Villanueva et al., 1996.).
            The synthetic compound meso-tetraphenyl-porphyrin (TPP;5,10,15,20-tetraphenyl-21H,23H-porphine; Fig. 1, inset) is the simplest aryl derivative of the porphine ring system, and although phototoxic effects can be expected to occur for TPP, possible applications of this compound as photosensitizer seem to have been overlooked.
            In the present work we have used TPP incorporated into liposome vesicles in order to study:
                                                - Spectral features
                                                - Microscopic localization in cultured HeLa cells
                                                - Dark toxicity
                                                - Cell photosensitization
                                                - Morphological changes photoinduced, and
                                                - Photodynamic production of ¹O₂ in vitro.