title: Production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.
abstract: The increasing application of Ac-225 for cancer therapy indicates the potential need for its increased production and availability. The production of Ac-225 has been achieved using bremsstrahlung photons from an 18 MV medical linear accelerator (linac) to bombard a Ra-226 target. A linac dose of 2800 Gy produced about 64 microCi of Ra-225, which decays to Ac-225. This result, while consistent with the theoretical calculations, is far too low to be of practical use. A more powerful linac is required that runs at a higher current, longer pulse length and higher frequency for practical production. This process could also lead to the reduction of the nuclear waste product Ra-226.
authors.affiliation: Centre for Experimental Radiation Oncology, St George Cancer Care Centre, Gray Street, Kogarah, NSW 2217, Australia. gmel@tpg.com.au
authors.forename: G
authors.initials: G
authors.lastname: Melville
authors.forename: H
authors.initials: H
authors.lastname: Meriarty
authors.forename: P
authors.initials: P
authors.lastname: Metcalfe
authors.forename: T
authors.initials: T
authors.lastname: Knittel
authors.forename: B J
authors.initials: BJ
authors.lastname: Allen
mesh_terms: D000186:Actinium / Q000737:chemistry*; D001918:Brachytherapy; D010315:Particle Accelerators; D017785:Photons; D011868:Radioisotopes; D019275:Radiopharmaceuticals / Q000737:chemistry; D011883:Radium / Q000737:chemistry*
chemical_list: D011868:Radioisotopes; D019275:Radiopharmaceuticals; D000186:Actinium; D011883:Radium