Institution: | 1. Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France
National Institute of Applied Sciences and Technology, Carthage University, EcoChimie Laboratory, Tunis, Tunisia
These authors contributed equally to this work.;2. MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510006 P. R. China;3. Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Laboratory for Inorganic Chemical Biology, 75005 Paris, France;4. Université de Paris, Institut de physique du globe de Paris, CNRS, 75005 Paris, France;5. Cellular and Molecular Imaging Platform, US 25 Inserm, UMS 3612 CNRS, Faculté de Pharmacie de Paris, Université Paris Cité, 75006 Paris, France;6. Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland;7. National Institute of Applied Sciences and Technology, Carthage University, EcoChimie Laboratory, Tunis, Tunisia |
Abstract: | Five osmium(II) polypyridyl complexes of the general formula Os(4,7-diphenyl-1,10-phenanthroline)2 L ]2+ were synthesized as photosensitizers for photodynamic therapy by varying the nature of the ligand L . Thanks to the pronounced π-extended structure of the ligands and the heavy atom effect provided by the osmium center, these complexes exhibit a high absorption in the near-infrared (NIR) region (up to 740 nm), unlike related ruthenium complexes. This led to a promising phototoxicity in vitro against cancer cells cultured as 2D cell layers but also in multicellular tumor spheroids upon irradiation at 740 nm. The complex Os(4,7-diphenyl-1,10-phenanthroline)2(2,2′-bipyridine)]2+ was found to be the most efficient against various cancer cell lines, with high phototoxicity indexes. Experiments on CT26 tumor-bearing BALB/c mice also indicate that the OsII complexes could significantly reduce tumor growth following 740 nm laser irradiation. The high phototoxicity in the biological window of this structurally simple complex makes it a promising photosensitizer for cancer treatment. |