Iodine-124 or 124I is an isotope of iodine. This isotope is not stable and therefore is radioactive, also called a radioisotope. It has a half-life of 4.18 days. Modes of Decay: 74.4% electron capture, 25.6% positron emission. 124I decays to 124Te.
Iodine-124 is used in medicine as a radiotracer in the body. It can be chemically bonded to a pharmaceutical and injected into the body. Positron Emission Tomography or PET is used to visualize the isotope in the body. Visualization is possible in PET because of the positron release by the iodine nucleus.
Iodine-124 can be made by numereous nuclear reactions via a cyclotron. The most common starting material used is 124Te.