Radionuclide Production and Radioactive Decay

Abstract

Abstract Radionuclide production and radioactive decay are two important factors for the development and use of radiopharmaceuticals for nuclear medicine imaging and radiotherapy applications. Sufficient quantities of the radionuclides used in medicine must be available on a routine basis at a reasonable cost. The radioactive ingredient must be sufficiently pure (both radiochemical and radionuclidic) and have enough activity to provide the therapeutic activity or the image information. The selection of a particular radionuclide for a specific application is determined by the radioactive decay properties (half‐lives, particle emission(s), particle energies, photon emissions, photon energies) and the behavior of the radionuclide in the body. Imaging applications require emission of penetrating radiations (gamma or positron annihilation photons), whereas radiotherapy applications require emission of short‐ range, high linear energy transfer (LET) radiations (alpha, beta, Auger electrons). Therapeutic radionuclides should not have significant emissions of penetrating radiations (gamma or positron annihilation photons), however, low abundance gamma emissions allow tracking of the in vivo therapeutic dose and dosimetry calculations. The factors of radioactive decay and radionuclide production are discussed, with examples and emphasis being on those radionuclides with applications to nuclear medicine.