Photo-activation of ruthenium-decorated upconverting nanoparticles
Metal-based prodrugs based on ruthenium(II) polypyridyl complexes have proven to be very suitable for application in both photodynamic therapy (PDT) and photo-activated chemotherapy (PACT).
- Meijer, M.S.
- 17 december 2018
- Thesis in Leiden Repository
Metal-based prodrugs based on ruthenium(II) polypyridyl complexes have proven to be very suitable for application in both photodynamic therapy (PDT) and photo-activated chemotherapy (PACT). As most of these complexes unfortunately require poorly-penetrative, potentially-toxic blue light for their photo-activation, a lot of research effort has been dedicated to the development of prodrug systems that can be activated using near-infrared light, which is less harmful and penetrates deeper into human tissue. Thulium-doped upconverting nanoparticles (UCNPs) produce the desired blue light upon excitation with near-infrared light, allowing for the development of a drug delivery system in which ruthenium prodrugs are activated with near-infrared light. This thesis deals with the development of several new photo-activatable ruthenium polypyridyl complexes and the investigation of their photochemistry. Furthermore, a multicentre comparative study of the upconversion quantum efficiencies of LiYF4 UCNPs is reported. Finally, it describes the formation of water-dispersible UCNPs decorated with the newly-developed ruthenium complexes, as well as their stability in aqueous media and the successful photo-activation of the surface-bound ruthenium complexes using near-infrared light. The work has resulted in new insights into the design principles that are essential for the successful development of photo-activatable ruthenium-decorated upconverting nanoparticles.