Cation Exchange Protocol to Radiolabel Rare-Earth Nanoparticles with Yttrium-90 for Radiotherapy and for Magnetic Resonance Imaging
Nisarg Soni, Ana Maria Panaite, Tuhin Samanta, Giulia Nucci, Emille M. Rodrigues, Teresa Pellegrino
Abstract
High Resolution Image Download MS PowerPoint Slide Internal radiation therapy (iRT) is an emerging therapeutic approach based on high-energy radionuclide implants categorized as alpha or beta particles placed directly into the tumor to induce cancer cell damage. This work focuses on the development of a unique approach for incorporating β-emitter yttrium-90 ( 90 Y) radionuclides via a cation exchange method into lanthanide-based nanoparticles (NPs), consisting of NaLnF 4 composition (Ln = Gd, Lu). The proposed method, thanks to the principle of cation exchange, is a straightforward protocol that involves just the mixing of water-stabilized NPs and radionuclides in aqueous environments at room temperature and, upon a short incubation time, enables the exchange of Gd or Lu ions with 90 Y with high efficiency. The radiotherapeutic effect of cation-exchanged NaLnF 4: 90 Y is here proven on glioblastoma cell lines with significant cytotoxicity, with the NaLnF 4: 90 Y NPs, while no intrinsic cytotoxicity was seen for nonradiolabeled NPs at the same material dose. Moreover, in the case of NaGdF 4 NPs, the gadolinium ions functioning as a T 1 contrast agents for magnetic resonance imaging (MRI) enables to track the cation exchange protocol by MR signal enhancement during the ion incorporation: indeed, the Y 3+ replacement with Gd enables the release of Gd 3+, which enhances the water exposure of Gd ions and, in turn, the enhancement of the T 1 MRI signal.