Rapid and automated production of [68Ga]gallium chloride and [68Ga] Ga-DOTA-TATE on a medical cyclotron

Introduction: The demand for Gallium-68 (Ga-68) for labelling PET radiopharmaceuticals has increased over the past few years. Ga-68 is obtained through the decayed parent radionuclide Ge-68 using commercial Ge-68/Ga-68 generators. The principal limitation of commercial Ge-68/Ga-68 generators is that only a limited and finite quantity of Ga-68 (<1.85 GBq at start of synthesis) may be accessed. The focus of this study was to investigate the use of a low energy medical cyclotron for the production of greater quantities of Ga-68 and to develop an automated and rapid procedure for processing the product. Methods: Enriched ZnCl2 was electrodeposited on a platinum backing using a NH4Cl (pH 2-4) buffer. The Zn target was irradiated with GE PETtrace 880 at 35 mu A and 14.5 and 12.0 MeV beam energy. The irradiated Zn target was purified using octanol resin on an automated system. Results: Following the described procedure, Ga-68 was obtained in 6.30 +/- 0.42 GBq after 8.5 min bombardment and with low radionuclidic impurities (Ga-66 (<0.005%) and Ga-67 (<0.09%)). Purification on a single octanol resin gave 82% recovery with resulting [Ga-68]GaCl3 obtained in 3.5 mL of 0.2 M HCl. [Ga-68]GaCl3 production from irradiation to final product was <45 min. To highlight the utility of the automated procedure, [(68)G]Ga-DOTA-TATE labelling was incorporated to give 1.56 GBq at EOS of the labelled peptide with RCY of >70%. Conclusions: A straightforward procedure for producing Ga-68 on a low energy medical cyclotron was described. Current efforts are focus on high activity production and radiolabelling using solid target produced Ga-68. Crown Copyright (C) 2019 Published by Elsevier Inc. All rights reserved.