Practical aspects of 153Gd as a radioactive source for use in brachytherapy

Abstract

The goal of this study was to investigate the production, purification and immobilization techniques for a ¹⁵³Gd brachytherapy source. We have investigated the maximum attainable specific activity of ¹⁵³Gd through the irradiation of Gd₂O₃ enriched to 30.6% ¹⁵²Gd at McMaster Nuclear Reactor. The advantage of producing ¹⁵³Gd through this production pathway is the possibility to irradiate pre-sealed pellets of ¹⁵²Gd enriched Gd₂O₃, thereby removing the need to perform chemical separation with large quantities of radio-impurities. However, small amounts of long-lived impurities are produced from the irradiation of enriched ¹⁵²Gd targets due to traces of Eu in the sample. If the amount of impurities produced is deemed unacceptable, ¹⁵³Gd can be isolated as an aqueous solution, chemically separated from impurities and loaded onto a sorbent with a high affinity for Gd before encapsulation.

Keywords: (153)Gd; Brachytherapy; Radiochemical separation; Radionuclide production; Specific activity; Thermal neutron capture cross section.