Production and quality control of radioactive yttrium microspheres for medical applications

In this paper, a method for production of yttrium silicate microspheres is reported. Yttrium silicate microspheres with approximate sizes of 20–50 µm were obtained when an aqueous solution of Y(NO3)3 was added to tetraethyl orthosilicate (TEOS) and was pumped into silicone oil under constant stirring. The shapes of the particles produced by the proposed method were regular and nearly spherical. The spherical shapes, composition and element distribution were investigated by scanning electron microscopy (SEM), carbon/sulfur analysis and SEM/EDS mapping analysis. Paper chromatography was used to identify radiochemical impurities in the radioactive microspheres. The radionuclide purity was determined using a gamma spectrometry system and an ultra-low-level liquid scintillation spectrometer. The results indicated that the proposed silicone oil spheroidization method is suitable for the production of yttrium silicate microspheres. - Highlights: • A new way for production of yttrium silicate microspheres is reported. • In the new way, the requiring high temperature is eliminated. • The glass plate crushing stage is eliminated. • Because of the crust of silicon around these microspheres, this method is suitable for the production of radioactive seed sources for implantation in tumors and cancer tissues