Cancer is a challenging disease to treat, regarding treatment efficiency and side-effects. To overcome these problems, extensive studies are exploring therapies with reduced side-effects, such as photodynamic therapy (PDT). PDT has advantages over conventional therapies, however its dependence on light limits it to treating tumors under the skin/ outer lining of organs . We have developed new photosensitizers self-activated intracellularly with tumor-selectivity based on chemiluminescent reactions involving a cancer marker. The photosensitizer is directly chemiexcited to a triplet excited state generating singlet oxygen, without an external light source. Thus, we aimed to develop self-activating photosensitizers which can be used for light-free photodynamic therapy, eliminating its light-related restrictions [2,3]. Cytotoxicity assays with breast and prostate cell lines showed that the novel photosensitizers possess significant toxicity toward tumor cells, while not affecting normal cells. Besides we compared the activity of these compounds with standard treatments, finding higher cytotoxicity .
Projects PTDC/QUI-QFI/2870/2020 and UIDB/00081/2020. C.M. acknowledges FCT for the PhD grant (SFRH/BD/143211/2019).
 M. Magalhães, C. G. Esteves, and L. Pinto, Chemphyschem, 17, 2016, 2286 – 2294.
 Luís Pinto da Silva , Ara Núnez-Montenegro , Carla M. Magalhães , Paulo J.O. Ferreira, Diana Duarte , Patricia Gonzalez-Berdullas, Jose E. Rodríguez-Borges, Nuno Vale, Joaquim C.G. Esteves da Silva , J. Med.Chem, 183, 2019, 111683.
 Luís Pinto da Silva , Carla M. Magalhães , Ara Núñez-Montenegro , Paulo J.O. Ferreira, Diana Duarte, José E. Rodríguez-Borges, Nuno Vale,Joaquim C.G. Esteves da Silva, Biomolecules, 9, 2019, 384.