Abstract
Positron emission tomography (PET) has emerged as a vital molecular imaging modality providing metabolic insights that are essential for the diagnosis and treatment of disease. Among the many useful applications of PET, imaging of infection has gained much traction in the last decade. To this end, we describe the synthesis and in vitro evaluation of D-[methyl-11C]-methionine, a potent metabolic tracer for living bacteria. D-[methyl-11C]-methionine was synthesized from [11C]methyl iodide ([11C]CH3I) using an in-loop synthesis method in an automated synthesis module. The radiotracer was analyzed by chiral high-performance liquid chromatography (HPLC) to determine its radiochemical identity and purity and then subjected to in vitro analysis using a rapid method to determine uptake in bacteria cells. The workflow described demonstrates the importance of communication and time management when developing new radiotracers, especially with short half-life isotopes such as carbon-11 (11C) (t1/2 = 20.4 min).