ABSTRACT
Copper-67 (67Cu) has physical characteristics useful for both therapy and imaging. However, its applicability has been hindered by the complexity of obtaining large quantities of a product with high specific activity. With the advancement of 67Cu production methods, suitable radioisotope carriers are sought. Lanthanide phosphate nanoparticles have demonstrated their multifunctional characteristics for biomedical applications and, more recently, their potential in radiopharmaceuticals. Thus, we produced luminescent lanthanide phosphate nanoparticles with core and core-shell structures, incorporating 67Cu during their synthesis. The nanoparticles exhibited hexagonal crystalline structure and spherical morphology with sizes below 6 nm. The luminescent colloidal suspensions evidenced the characteristic 5D0-7FJ for Eu3+, providing the red color under UV light. A radiochemical yield of 67Cu >95% was obtained with both core and core-shell LaPO4:Eu. The core-shell nanoparticles reduced the release of 67Cu by a factor of â¼2 over that from the core, which continuously decreased with time. Multifunctional LnPO4 nanoparticles have the potential to be used as a carrier of single or multiple radioisotopes to enhance image-guided targeted nano-radiopharmaceutical therapy.