Radium-224 (²²⁴Ra) a highly targeted, alpha-emitting therapeutic agent in nuclear medicine, specifically engineered to destroy localized cancer cells while minimizing damage to surrounding healthy tissue. Radium-224 is an alkaline-earth metal isotope with a short half-life. As it decays, it emits high-energy alpha particles that cause fatal double-strand DNA breaks in nearby cancer cells. Because alpha particles possess a very short tissue range (only a few cell diameters), the destructive radiation remains tightly localized. Medical and Clinical Uses
Intraperitoneal Cancer Microparticles: The most prominent modern application for Radium-224 is in the form of Radium-224-labeled calcium carbonate microparticles. It treats peritoneal carcinomatosis, a highly aggressive metastatic spread originating from ovarian and colorectal cancers. The microparticles distribute across the abdominal lining, releasing alpha particles to eliminate microscopic residual tumor cells that standard surgery cannot remove.
Diffusing Alpha-Emitter Radiation Therapy: Radium-224 is deployed as the active core component in specialized intratumoral brachytherapy seeds. Once implanted, the Radium-224 decays and releases its gaseous daughter isotope, Radon-220. This gas continuously diffuses outward through the tumor matrix, creating a localized, highly uniform wave of alpha radiation that destroys the surrounding tumor tissue. This method is heavily studied for skin (cutaneous), mucosal, and soft tissue neoplasias.
Radionuclide Generators for Lead-212 / Bismuth-212: In radiopharmaceutical manufacturing, Radium-224 functions as a parent isotope in nuclear generator systems. Medical laboratories stock Radium-224 to routinely extract (or "milk") Lead-212 (²¹²Pb). Lead-212 is highly sought after for Targeted Alpha Therapy (TAT), where it is chemically bound to monoclonal antibodies or peptides to track down and obliterate microscopic cancer metastases throughout the bloodstream.
Characteristics Isotope Enrichment: > 98.00 Chemical Form: 224 Ra Molar mass: 224.02 g/mol CAS number: 13233-32-6
