Anhydrous F-18 labeled elemental fluorine for radiopharmaceutical preparation

Interest in fluorine-18 as a label in radiopharmaceutical studies has led to the development of a method for the production of decicuries of anhydrous ¹⁸F-F ₂ using the ²⁰Ne(d,α) ¹⁸F reaction. The amount of anhydrous ¹⁸F-F ₂ that can be removed from the target is a function of target pressure and decreasing with decreasing carrier concentration. At a target pressure of 24 atmospheres and a carrier concentration of 0.1% F ₂, nearly 95% of the theoretical yield of fluorine-18 produced can be removed and up to 85% delivered through a 10-m stainless steel tube to the reaction chamber. Other functions affecting yield, including target design, target-gas handling and purity, have been addressed. Thick target yields for 14.0- and 9.4-MeV deuterons on target were measured to be 82 and 67 mCi/μA at saturation. With the BNL 60-in. cyclotron, production of 600-800 mCi of ¹⁸F-F ₂ with a specific activity of ~10 mCi/μmole has been in effect since 1976.