Noun
English Wikipedia has an article on:fluorine-18Wikipedia
fluorine-18 (uncountable)
(physics) An artificial radioisotope of fluorine, 9F, having 9 protons and 9 neutrons, that is an important industrial source of positrons
At present, however, by far the most commonly used radiotracer in clinical PET scanning is fluorodeoxyglucose (also called FDG or fludeoxyglucose), an analogue of glucose that is labeled with fluorine-18. Source: Internet
The half-life of fluorine-18 is long enough that radiotracers labeled with fluorine-18 can be manufactured commercially at offsite locations and shipped to imaging centers. Source: Internet