In cyclotrons charged particles are circular accelerated to bombard atoms. Short-lived positron-emitting isotopes are produced for Positron Emission Tomography (PET) imaging (e.g. F-18).

See also Linear Accelerator, Metastable Condition, Meson, Fluorodeoxyglucose, Electric Polarization.

Decay chain or decay series is a series of decays that certain radioisotopes go through before reaching a stable form. For example, the production of technetium-99m (daughter nuclide with a half-life of 6 hours) from molybdenum-99 (parent nuclide with a half-life of 66 hours) in a generator is part of a decay chain.

See also Decay and Generator.

(FDG) Fluorodeoxyglucose F18 is a type of radioactive glucose (sugar). FDG is the most common radioisotope used in PET/CT scanning.

Gallium is a metal with the chemical symbol Ga and atomic number 31. Gallium salts such as gallium citrate and gallium nitrate (with the radioactive isotope 67Ga) are used as radiopharmaceuticals in diagnostic nuclear medicine procedures, for example abscess or inflammation scintigraphy.

A generator is used in nuclear medicine to provide a radioisotope used for a scintigraphic procedure. A generator contains a radionuclide (e.g. molybdenum) that decays to another radionuclide (decay product, e.g. technetium) that can be extracted and used. The original radionuclide is firmly bound in the generator and remains behind.

See also Eluate