ion123Iodine-123 (123 I) is a radioactive isotope of iodine used in nuclear medicine imaging, including single-photon emission computed tomography (SPECT) or SPECTCT exams. The isotope's half-life is 13.2232 hours; [1] the decay byiodide ion (123 i) dtxsid40988959; 123i-(~123~i)iodide; i 123 mini; dtxcid701416091; iodine-123(1-) 69239-56-1; i-123; xmbwdfgmswqbca-ahcxrolusa-m; db09420; q3801335