Post-Processing via Cation Exchange Cartridges: Versatile Options

Abstract

New ⁶⁸Ge/⁶⁸Ga radionuclide generators provide the positron emitter ⁶⁸Ga (T½ = 67.7 min) as an easily available and relatively inexpensive source of a PET nuclide for labeling of interesting targeting vectors. However, currently available “ionic” ⁶⁸Ge/⁶⁸Ga radionuclide generators are not necessarily optimized for the routine synthesis of ⁶⁸Ga-labeled radiopharmaceuticals in a clinical environment. Post-processing of ⁶⁸Ge/⁶⁸Ga generators using cation exchange resins provides chemically and radiochemically pure ⁶⁸Ga with 97±2% within less than 4 min, with ⁶⁸Ge almost completely removed, and ready for online labeling. This simple, fast, and efficient technology can be extended for new applications. The options are (a) to transfer ⁶⁸Ga from the cation exchange resin onto an anion exchange resin, to remove acetone, and to further purify the ⁶⁸Ga, (b) to obtain ⁶⁸Ga in pure non-aqueous solution via ⁶⁸Ga(acac)₃ as a synthon for syntheses in organic solvents, and (c) to create an option toward instantaneous determination of ⁶⁸Ge breakthrough, what may be required prior to the release of ⁶⁸Ga radiopharmaceutical preparations.