This research project proposes the synthesis, structural characterization and study of photochemical and photophysical behavior of a series of ruthenium complexes with bulky polypyridine-type ligands (2,2'-biquinoline, 4,4'-diphenyl-2,2'-bipyridine, 4'-chloro-2,2':6',2''-terpyridine and 2,2':6',2''-terpyridine) containing non-steroidal anti-inflammatory drugs (NSAIDs) coordinated. Aiming the usage of such complexes as candidates for photodynamic therapy (PDT) metallodrugs, we propose spectroscopic studies, both of ground and excited states, photorelease of biologically active molecules assays, and investigation on reactive oxygen species formation by the complex. Cytotoxicity (in presence and absence of light) for B16F10 murine melanoma cells (a cell model for skin cancer) will be evaluated by the end of the work to assess the feasibility of such systems as metallodrugs in PDT. The usage of bulky polypyridine-type ligands over classic ones is justified for two reasons: the photochemical lability such ligands promote on the other coordination sites of the complex and the far red-shifted absorption band associated with the d-d electronic transition, in such region where skin presents higher absorptivity. Both properties are due to electronic effects originated from the high octahedral geometry distortion promoted by the bulkier ligands. With these properties, such complexes are promising for usage in PDT and for this reason, will be thoroughly studied in this work.
News published in Agência FAPESP Newsletter about the scholarship: