terbium-155

Terbium-155 is a radioactive lanthanide isotope with a half-life of 5.32 days, primarily investigated as a diagnostic radiopharmaceutical for Single Photon Emission Computed Tomography (SPECT) imaging in oncology. It is a key component of the "theranostic quartet" of terbium isotopes (Tb-149, Tb-152, Tb-155, and Tb-161), which share identical chemical properties, enabling the use of the same targeting vector for both diagnosis and therapy. Terbium-155 emits low-energy photons (87 keV and 105 keV) ideal for high-resolution SPECT imaging and also emits Auger electrons, which may provide therapeutic potential for small clusters of cancer cells. The isotope is typically chelated to tumor-targeting biomolecules, such as somatostatin receptor ligands (e.g., DOTATATE) or folate derivatives, using DOTA-based chelators. Current efforts, such as the "Terbium for Life" project, aim to establish a reliable European supply chain for this isotope using cyclotron and mass-separation technologies.

Other names

Tb-155Tb155Tb 155155Tbterbium-155 radionuclideterbium155 radionuclideterbium 155 radionuclide