Reliable One‐Pot Automated Preparation of [ 11 C]SL25.1188 for Use in Clinical Imaging Studies

We clinically investigated ( S )‐5‐methoxymethyl‐3‐[6‐(4,4,4‐trifluorobutoxy)benzo[ d ]isoxazol‐3‐yl]oxazolidin‐2‐[ 11 C]‐one ([ 11 C]SL25.1188) as a positron emission tomography tracer for imaging monoamine oxidase B. To perform clinical imaging studies at our institute, we established a routine method for preparing the [ 11 C]SL25.1188 injection using a one‐pot [ 11 C]CO 2 fixation method. We successfully prepared the [ 11 C]SL25.1188 injection using a 11 C‐labeling synthesizer and sterile isolator. The radiosynthesis time and decay‐corrected radiochemical yield based on [ 11 C]CO 2 were below 30 min and 49% ± 10% postirradiation ( n = 104), respectively. At the end of synthesis ( n = 104), the molar activity was 180 ± 57 GBq/μmol, and the radiochemical purity exceeded 99%. The results of [ 11 C]SL25.1188 injection complied fully with our in‐house quality control and quality assurance criteria, confirming a reliable supply of high‐quality [ 11 C]SL25.1188 formulation with adequate radioactivity for use in clinical imaging studies.