Green light-induced apoptosis in cancer cells by a tetrapyridyl ruthenium prodrug offering two trans coordination sites

apoptosis. Meanwhile, very low singlet oxygen quantum yields (∼1-2%) and cell-free DNA binding studies conclude that light-induced cell death is not caused by a photodynamic effect, but instead by the changes induced in the coordination sphere of the metal by light, which modifies how the metal complexes bind to biomolecules.