Synthesizing small-sized monodisperse molybdenum nanoparticles as potential precursors for medical radioisotopes

Abstract

Molybdenum-99 (99Mo) is used to produce technetium-99 m (99mTc), one of the most used medical radioisotopes in the world. 99Mo is currently created by fission of uranium-235 (235U) in a small number of research nuclear fission reactors. Several problems related to the use of 235U as primary source is causing a global 99Mo generation crisis. Therefore, we are facing the need of finding new viable and safe production alternatives. Neutron activation of molybdenum is a promising candidate in which the ideal target for 99Mo production are small monodisperse molybdenum nanoparticles (Mo NPs). However, the reported procedures for the obtention of Mo NPs present either the lack of simplicity of the employed synthetic methods or the inappropriate size and monodispersity of the synthesized Mo NPs. Here, we report a simple synthetic procedure for the obtention of small-sized monodisperse metallic Mo NPs. In the studied conditions, thermal decomposition of Mo(CO)6 produced oleylamine coated Mo NPs. The oleylamine layer was included with the purpose of avoiding oxidation. Although an oxide patina was still formed on the surface of the Mo NPs, the core remains in a metallic phase after several weeks from its production, as it was confirmed by X-ray photoelectron spectroscopy analysis (XPS). The described synthetic procedure provides a simple method for the obtention of Mo NPs with optimum characteristics as non-fission method for 99Mo production.