Efficient photodynamic therapy of cancer using chemotherapeutic porphyrin–ruthenium metalla-cubes

Two cationic arene ruthenium metalla-cubes have been evaluated as potential dual photosensitizers and chemotherapeutics. In the dark, the complexes presented good cytotoxicity only towards melanoma and ovarian cancer cells, while the complexes exhibited excellent phototoxicities: The LD50 of the metalla-cubes being between 2 and 7J/cm2. These results suggest a dual synergistic effect with good properties of both the arene ruthenium chemotherapeutics and the porphyrin photosensitizers. Two cationic octanuclear metalla-cubes [Ru8(η6-C6H5Me)8(tpp-H2)2(dhbq)4]8+ and [Ru8(η6-p-iPrC6H4Me)8(tpp-H2)2(dhbq)4]8+ were prepared and evaluated as dual photosensitizers and chemotherapeutics in cancer cells. In the dark, the complexes presented high cytotoxicity towards only melanoma and ovarian cancer cells. However, the complexes exhibited good phototoxicities toward all cancer cells (1μM concentration, LD50=2–7J/cm2), thus suggesting a dual synergistic effect with good properties of both the arene ruthenium chemotherapeutics and the porphyrin photosensitizers.