Photo- and X-ray Induced Cytotoxicity of CeF 3 -YF 3 -TbF 3 Nanoparticle-Polyvinylpyrrolidone-"Radachlorin" Composites for Combined Photodynamic Therapy

The Ce Y Tb F nanoparticles with a CeF hexagonal structure were synthesized using the co-precipitation technique. The average nanoparticle diameter was 14 ± 1 nm. The luminescence decay curves of the Ce Y Tb F nanoparticles (λ = 541 nm, D - F transition of Tb ) conjugated with Radachlorin using polyvinylpyrrolidone coating as well as without Radachlorin were detected. Efficient nonradiative energy transfer from Tb to the Radachlorin was demonstrated. The maximum energy transfer coefficients for the nanoparticles conjugated with Radachlorin via polyvinylpyrrolidone and without the coating were 82% and 55%, respectively. The average distance between the nanoparticle surface and Radachlorin was = 4.5 nm. The best results for X-ray-induced cytotoxicity were observed for the NP-PVP-Rch sample at the lowest Rch concentration. In particular, after X-ray irradiation, the survival of A549 human lung carcinoma cells decreased by ~12%.