Abstract: An 18F isotope-labeled FDG radiopharmaceutical is stabilized against degradation in radiochemical purity due to radiolysis using selected amounts of ethyl alcohol that depend on the activity concentration of the 18F with due regard to limits set by various pharmacopoeia standards. Any of the well-know production methods for the FDG may be used and the ethyl alcohol added at several stages, preferably as part of the standard hydrolysis step. This particular radiopharmaceutical is used extensively in diagnostic imaging with a Positron Emission Tomography technique.

Abstract: A process and apparatus for producing the 18F isotope from water enriched with the 18O isotope using high energy protons from a cyclotron. The apparatus has a cyclotron target cavity that is connected to a fluid loop that contains a water reservoir, pump, and pressure regulator. Water is continuously recirculated through the target cavity to increase reliability. After irradiation long enough to produce a desired amount of 18F, water in the target loop is diverted through an 18F extraction device before being returned to the target loop. The returning water may also be purified and additional water added to the target loop as needed to permit continuous irradiation and production of 18F.