Oxygen-18

Oxygen-18 (18O, Ω) is a natural, <a href="/facts/Stable_isotope/vgcdxgjA">stable isotope</a> of <a href="/facts/Oxygen/acyn6o8r">oxygen</a> and one of the <a href="/facts/Environmental_isotopes/Ud2voc2m">environmental isotopes</a>.
18O is an important precursor for the production of <a href="/facts/Fluorodeoxyglucose/bcLYHLvk">fluorodeoxyglucose</a> (FDG) used in <a href="/facts/Positron_emission_tomography/5SmcW6qz">positron emission tomography</a> (PET). Generally, in the <a href="/facts/Radiopharmaceutical/x3g6zbB6">radiopharmaceutical</a> industry, enriched water (H2Ω) is bombarded with hydrogen ions in either a <a href="/facts/Cyclotron/Q8APwhWm">cyclotron</a> or <a href="/facts/Linear_particle_accelerator/GIz6Uc4x">linear accelerator</a>, producing <a href="/facts/Fluorine-18/4VpH1NYh">fluorine-18</a>. This is then synthesized into FDG and injected into a patient. It can also be used to make an extremely <a href="/facts/Heavy_water/3dbSrTw5">heavy version of water</a> when combined with <a href="/facts/Tritium/HWSa6EHy">tritium</a> (<a href="/facts/Hydrogen/BoYHjl0J">hydrogen</a>-3): 3H218O or T2Ω. This compound has a density almost 30% greater than that of natural water.
The accurate measurements of 18O rely on proper procedures of analysis, sample preparation and storage.

Oxygen-18 open-in-new

Oxygen-18