RADIONUCLIDE GENERATORS TO PRODUCE THE IRIDIUM-194 BETA EMITTER

该项目调查了设计、制造、测试和

The project investigates the design, manufacturing, testing, and use of a novel radionuclide generator for biomedical applications. The generator has a long shelf-half-life, many years, and produces a 20 hour radionuclide daughter which emits high-energy beta particles that have suitable characteristics for labelling proteins through bifunctional chelates. In the 194Os/194 Ir generator containing the parent nuclei, 194Os, has a half-life of 6.0 years which beta-decays, EmaxB=100 keV, to the 19.15-hour 194Ir daughter. The 194Ir daughter decays with the emission of 2.2 Mev beta particles to the ground state of 194Pt (86%) and to the 328.5 keV first excited state with emission of 1.9 MeV beta particles (9.2%). There is a 328.5 keV first excited state with emission of 1.9 MeV beta particles (9.2%). There is a 328.5 keV gamma-ray which follows the decay of 194Ir with 13% absolute aboundance. The absence of high intensity gamma-rays in the decay of 194Ir, with the exception to the 328.5 keV, makes this beta emitter nuclei very attractive from the point of view of dosimetric considerations. On the other hand, the presence of 328.5 keV gamma-rays, makes 194Ir a superior nucleus to 90Y for tumor imaging. Preliminary calculations indicate that several mCi of the parent, 1940s, can be produced in a nuclear reactor by double neutron capture of an 1920s (natural aboundance of 41%) target. By using enriched 1920s, a two fold increase in the yield results and also reduces the production of impurities. The enriched Osmium-192 with enrichment factor of greater than 99% is purchased from Oak Ridge National Laboratory.