Nuclear Science


Medical Radioisotope

Staff members preparing Ac-225 in glove boxes for shipment to hospitals to support radiotherapy cancer clinical trials in multiple locations around the world.

ORNL’s Medical Radioisotope Program is focused on the development of improved reactor production and processing methods to provide medical radioisotopes, the development of new radionuclide generator systems, the design and evaluation of new radiopharmaceuticals for applications in nuclear medicine and oncology, and association with Medical Cooperative Programs throughout the world for further preclinical testing and clinical evaluation of agents developed at ORNL. The collective resources of ORNL, including access to the enriched stable isotope inventory, a High Flux Isotope Reactor (HFIR), hot cell and glove box processing capabilities, and a wide range of support functions required for research and radioisotope production provide unique capabilities for nuclear medicine research and therapeutic radioisotope production.

Another major ORNL area of medical radioisotope research includes production of the alpha-emitting radioisotope actinium-225, which is used in radiotherapy of cancer. Actinium-225 is routinely extracted from the thorium-229 stock, and ORNL is currently the largest supplier of this medical radioisotope supporting clinical trials around the world. Several pathways are being investigated to increase the supply of thorium-229 and actinium-225. These include recovering it from aged U-233, evaluating reactor production in the HFIR, and collaborating with Isotope Program accelerator production facilities at BNL and LANL. Research has also been conducted on production at the ORNL Holifield Radioactive Ion Beam Facility. Research and development on other alpha-emitting medical isotopes is also in progress.  Investigations on the feasibility of a new, multi-particle cyclotron facility for medical radioisotope R&D at ORNL are also underway.

For more information, contact:
Nuclear Security and Isotope Technology Division


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