Synthesis of [68Ga]Ga-PSMA-11 using the iMiDEV™ microfluidic platform

Abstract

We report herein the first production of [⁶⁸Ga]Ga-PSMA-11 based on a microfluidic disposable cassette using the iMiDEV™ synthesizer. The main steps of synthesis, ⁶⁸Ga-concentration on the cation exchange resin followed by a labelling step and lastly the formulation of the final product, were integrated within the cassette. ⁶⁸Ga-trapping and release were investigated using cassettes filled with MCX or PS-H⁺ beads. Optimal radiolabelling conditions were determined including the precursor amount (10 μg), temperature (95 °C), and reaction time (1 min) allowing us to achieve up to 99% radiochemical conversion rate of [⁶⁸Ga]Ga-PSMA-11. Fully-automated [⁶⁸Ga]Ga-PSMA-11 radiosynthesis on the cassette was carried out with an isolated radiochemical yield (RCY) of 46.5 ± 2.6% (n = 3, relative to starting [⁶⁸Ga]GaCl₃) in 19 min production time. Despite the additional investigation necessary to improve ⁶⁸Ga-release from micro-chamber R1, the developed method can potentially be applied to the labelling of other ⁶⁸Ga-radiopharmaceuticals on the microfluidic cassette iMiDEV™.