In view of the increasing demands for the currently available radiopharmaceuticals such as [15O]-water, 2-[18F]FDG, 6-[18F]FDOPA, (18F]cyclofoxy and new radiopharmaceuticals, it has become apparent that significant improvements in the current use of the Department's resources must be made. The primary goal of this work is the development of new techniques particularly suited to automation and simplification of radiopharmaceutical production and thereby provide more efficient use of instrumentation, time and personnel. Solid-phase techniques have been used extensively for radioincorporation of C-11 and F-18 nuclides, the reaction of radiolabeled intermediates in multi-step radiosyntheses and the purification of radiochemical intermediates by extraction. The incorporation of [18F]fluoride using modified SAX polystyrene-divinylbenzene resin has dramatically simplified the routine production of [18F]FDG (1). Modified SAX polystyrene-divinylbenzene has been used for the incorporation of [18F]fluoride into 3-acetyl-6-alpha-naltrexol triflate. Radiochemical yields are commensurate with those obtained by solution techniques (60%, EOB). The acylated radiochemical intermediate was deblocked by subsequent reaction over a second SAX polystyrene- divinylbenzene support and directly injected onto an HPLC for purification. The purified final product was isolated for formulation from HPLC eluent by extraction using a commercially available fluorocarbon membrane supported SAX resin. The application of solid-phase synthesis to simplify the production of other important PET radiopharmaceuticals and precursors will be investigated.
