Carbon-11 Production: Communication, Operations, Maintenance, Troubleshooting, and Analysis for Maintaining High-Grade Bombardment and Provisions of [¹¹C]Carbon Dioxide and Its Conversion to [¹¹C]Methyl Iodide.

Abstract

Incorporation of carbon-11 radiotracers for positron emission tomography (PET) imaging requires close coordination between cyclotron operation, radiochemistry production, quality control, and clinical administration. A persistent challenge exists is the minimization of the carbon-12 isotopologue mass of the radiotracer, which reduces molar activity and can compromise PET image quality. This challenge can be particularly acute at facilities where cyclotron operation and carbon-11 radiochemistry are realized by separate organizations with distinct operational priorities. Here, we describe how the Radiochemistry Group at New York University Grossman School of Medicine and Siemens Healthineers have developed an integrated operational framework for consistent, high-quality carbon-11 production within an academic-industry partnership. Cyclotron target maintenance and conditioning protocols, remote chemistry module maintenance schedules, a validated radio-HPLC method (UV LOD = 0.9 µg/mL, UV LOQ = 3.0 µg/mL) for trending methyl iodide isotopologue mass, and structured inter-team communication protocols are presented in this manuscript. Quality analysis demonstrates molar activities consistently exceeding the recommended minimum of 40 GBq/µmol for reversibly binding radiotracers used in human PET studies. This work is intended as a practical resource for radiochemists, cyclotron engineers, and facility managers working to establish or improve institutional carbon-11 programs.