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 194-0s/194-Ir generator containing the parent nuclei, 194- 0s, has a half-life of 6.0 years which beta-decays, EmaxB=100 KeV, to the 19.15-hour 194-Ir daughter. The 194-Ir daughter decays with the emission of 2.2 MeV beta particles to the ground state of 194- Pt (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 194-Ir with 13% absolute abundance. The absence of high intensity gamma-rays in the decay of 194-Ir, 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 194-Ir a superior nucleus to 90-Y for tumor imaging. Preliminary calculations indicate that several mCi of the parent, 194-0s, can be produced in a nuclear reactor by double neutron capture of an 192-0s (natural abundance of 41%) target. By using enriched 192-0s, 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.
