The in vitro cytotoxicity of metal-complexes of porphyrin sensitizer intended for photodynamic therapy

Abstract

The sulphonated derivatives of porphyrins (e.g. TPPS4) are hydrophilic photosensitizers and have certain advantages like fully known structures and the possibility of synthetic production.The aim of this work was to study in vitro cytotoxicity and to compare the new photosensitizer MgTPPS4 with TPPS4 and its other metal-complexes (ZnTPPS4, PdTPPS4) on human skin melanom and mouse fibroblast cell lines. A photodynamic treatment was induced by light emitting diodes with three different total doses (1, 5 and 10J/cm2).For proper analysis and understanding of cell behavior after the administration of sensitizers, a complex battery of in vitro tests including the production of reactive oxygen species, the MTT viability test, a comet assay, a cell cycle and a type of cell death determination were used.We discovered that the most suitable photosensitizer is ZnTPPS4 because it had the biggest lethal influence on melanoma cells and the lowest lethal influence on fibroblast cells. The second most effective photosensitizer seemed to be MgTPPS4. On the basis of our results we can also assume that there is a higher accumulation of photosensitizer in a tumorous cell line. The higher concentration of photosensitizer and light dose resulted in more reactive oxygen species production and found more cells undergoing necrosis.