Automated GMP-production of α-[11 C]methyl-L-tryptophan using a tracer production system (TPS).

The radiosynthesis and GMP validation of [11 C]AMT for human use are described. Three consecutive batches were produced giving 940-3790 MBq (4%-17% RCY, decay corrected, based on [11 C]CO2 ) of the tracer. The molar activity at the end of synthesis was 19 to 35 GBq/μmol, the radiochemical purity was ≥98%, and the enantiomeric purity was >99%. While the synthesis method was automated using a new generation of synthesis equipment, tracer production system developed in house, the method should be readily applicable to other synthesis platforms with minor modifications.