en.Wedoany.com Reported - Recently, the China Institute of Atomic Energy (CIAE) has successfully completed the full process flow for the preparation of the emerging medical isotope terbium-161 (161Tb), producing a 100 millicurie high-purity sample. Tests show that the sample has a radionuclidic purity as high as 99.9% and radiochemical purity of 99%, with impurity concentrations of iron, copper, zinc, etc. at the ppb level (10-11 to 10-7). This marks that the China National Nuclear Corporation (CNNC) has successfully mastered the radionuclidic purity control technology for medical terbium-161, and its separation and purification process has set a new domestic record for recovery rate and impurity removal rate for this nuclide, laying a solid foundation for the domestic production of high-purity terbium-161.
Terbium-161 is a new-generation theranostic medical radioisotope, combining both imaging diagnosis and targeted therapy: on one hand, it can effectively destroy solid tumors by emitting beta rays; on the other hand, it releases a large number of additional Auger electrons and internal conversion electrons, precisely damaging the DNA of cancer cells, making it particularly effective at eliminating micrometastases. Terbium-161 delivers a higher local radiation dose to tumors while causing less damage to normal organs and tissues, offering significant clinical value and application prospects in the radiotherapy of small tumors, and is expected to become a boon for patients with neuroendocrine tumors, prostate cancer, and other conditions.
Medical terbium-161 has extremely high requirements for radionuclidic purity and radiochemical purity, and the core challenge in its preparation lies in separating terbium-161 from the precursor material gadolinium-160, radioactive impurities, and metal ion impurities such as iron and copper. Currently, international methods for extracting terbium-161 have been established, but the separation and purification process suffers from relatively low recovery rate and impurity removal rate.
Facing this challenge, the Department of Radiochemistry at CIAE, targeting the frontier nuclide market, adopted the advanced research and development management model of Integrated Product Development (IPD), and independently utilized stable isotopes of gadolinium, terbium, and dysprosium to preliminarily establish a complete process chain covering gadolinium-160 target preparation, irradiation, and separation and purification. The team successively completed irradiation experiments on natural and high-abundance enriched gadolinium targets, and successfully conducted multiple separation and purification hot tests, achieving the full process flow for terbium-161 preparation, and confirming that key indicators such as chemical recovery rate and impurity removal rate meet design requirements.
In the next step, CIAE will further solidify the nuclide preparation process and actively promote the development of large-scale preparation technology and the translation of results, contributing to the high-quality and sustainable development of China's nuclear medical industry.
