ALA-containing transparent applicators on the basis of biodegradable polymers for photodynamic therapy of superficial malignancies

摘要

The efficiency of photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) is essentially determined by an optimal choice of sensitization means, among which the application method is one of the most perspective due to high permeability of a skin for 5-ALA. The aim of present work is optimization of sensitization process with ALA. We have used the possibility of 5-ALA transparency in applicator (outside of tissue) while protoporphyrin-IX, formed in sensitized tissue, has sufficient absorption for providing PDT. We have developed 5-ALA containing applicator on the basis of transparent biodegradable polymers, which serve as a programmed source of 5-ALA in the zone of their contact with pathological tissue. The investigations carried out on mice with the solid form of leucosis p-388, have shown that developed applicator provides effective sensitization of pathological tissue, supporting high concentration of photosensitiser in tissue during the whole time of application (up to week). The experiments in vivo have demonstrated high efficiency of PDT. The preliminary clinical researches allow to draw a conclusion about its perspectivity for photodynamic treatment of skin malignancies.