Speaker
Description
Rare-earth-based fluoride nanocomposite materials represent a promising platform for applications in radiation-based cancer therapies, particularly in the context of X-ray induced photodynamic therapy (XPDT) [1,2]. Due to their scintillation properties, these materials are capable of converting the ionizing radiation into UV/visible photons, enabling in situ activation of photosensitizers within tumor tissue. A key requirement for biomedical application of the nanoparticles is their low dark toxicity, together with the ability to provide enhanced radiation-induced biological effects upon excitation by ionizing radiation.
Our work focuses on the in vitro evaluation of the cytotoxicity of Tb-doped $\text{LaF}_3$ and $\text{(Ce,La)F}_3$ nanoparticles using the PANC-1 pancreatic adenocarcinoma cell line. The $\text{LaF}_3\text{:Tb}^{3+}$ (5%) and $\text{Ce}_{0.15}\text{La}_{0.80}\text{F}_3\text{:Tb}^{3+}$ (5%) systems were selected based on the previous comparative studies of Ce- and Tb- co-doped lanthanum fluorides, which identified these compositions as promising candidates with prospective physicochemical and optical properties relevant to XPDT [3, 4]. Dark toxicity experiments were assessed over a range of nanoparticle concentrations (up to 1,5 mg/mL) to define a safe concentration window for subsequent experiments. To evaluate nanoparticle-related effects under irradiation, experiments were performed at different radiation doses using irradiation in the SCIOX beam X-ray cabinet.
This study represents an initial step towards the development of $\text{(Ce,La)F}_3$-based scintillating nanocomposites for XPDT treatment. The obtained results will serve as a basis for future experiments combining nanoparticles with photosensitizers and ionizing radiation to achieve the desirable therapeutic outcome resulting from the dual effect of ionizing radiation in the course of radiotherapy: (1) the direct damage and (2) the damage caused by photosensitizer-mediated production of reactive oxygen species.
[1] A. Dorokhina, et al. “Solvothermal synthesis of $\text{LaF}_3\text{:Ce}$ nanoparticles for use in medicine: luminescence, morphology and surface properties,” Ceramics 6, 1 (2023).
[2] K. Popovich, et al. “Preliminary study on singlet oxygen production using $\text{CeF}_3\text{:Tb}^{3+}\text{@SiO}_2$-PpIX,” Radiat. Meas. 90 (2016).
[3] X. Lytvynenko, et al. “Optimization of the Fabrication of Luminescent Nanocrystalline $\text{Ce}_x\text{La}_{1-x}\text{F}_3\text{:Tb}^{3+}$ for XPDT Applications,” IEEE Trans. Nucl. Sci. 72 (7) (2025).
[4] X. Lytvynenko, et al. “Composition-dependent properties of $\text{Ce}_x\text{La}_{0.95-x}\text{Tb}_{0.05}\text{F}_3$ nanopowders tailored for X-ray photodynamic therapy and cathodoluminescence imaging,” Radiat. Meas. 189 (2025).
This work has been funded by a grant from the Programme Johannes Amos Comenius under the Ministry of Education, Youth and Sports of the Czech Republic SENDISO, project No. CZ.02.01.01/00/22_008/0004596; by the Ministry of the Interior of the Czech Republic (OPSEC programme), project No. VK02020047; European Union’s Horizon Europe’s Marie Skłodowska-Curie Actions - Co-funding of Regional, National and International Programmes (MERIT - Grant Agreement No. 101081195). This work was performed within the frame of Crystal Clear Collaboration.