Automated synthesis of [18F](2S,4R)-4-fluoroglutamine on a GE TRACERlab™ FX-N Pro module

Abstract Glutamine (Gln) and its analogues may serve as imaging agents for tumor diagnosis using positron emission tomography (PET), especially for tumors with negative [ 18 F]FDG scan. We report the first automated synthesis of [ 18 F]( 2S , 4R )-4-fluoroglutamine ([ 18 F]FGln) on a GE TRACERlab™ FX-N Pro module. [ 18 F]FGln was obtained in 80±3 min with a radiochemical yield of 21±3% (n=5, uncorrected). The radiochemical purity was >98%, and optical purity 90±5%. The synthesis is highly reproducible with good chemical purity, radiochemical yield, and is suitable for translation to cGMP production.