Iodine-123

Iodine-123, 123I
General
Symbol123I
Namesiodine-123, 123I, I-123,
radioiodine
Protons (Z)53
Neutrons (N)70
Nuclide data
Natural abundance0
Half-life (t1/2)13.2232(15) h[1]
Isotope mass122.9055898(40)[2] Da
Parent isotopes123Xe
Decay products123Te
Decay modes
Decay modeDecay energy (MeV)
electron capture0.159 (159 keV)
Isotopes of iodine
Complete table of nuclides

Iodine-123 (123I) is a radioactive isotope of iodine used in nuclear medicine imaging, including single-photon emission computed tomography (SPECT) or SPECT/CT exams. The isotope's half-life is 13.2232 hours;[1] the decay by electron capture to tellurium-123 emits gamma radiation with a predominant energy of 159 keV (this is the gamma primarily used for imaging). In medical applications, the radiation is detected by a gamma camera. The isotope is typically applied as iodide-123, the anionic form.

  1. ^ a b Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  2. ^ Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf.