Simple and effective method for producing [11C]phosgene using an environmental CCl4 gas detection tube

Abstract

Carbon-11-labeled phosgene is an important labeling precursor for PET molecular probes. Despite the usefulness of [(11)C]phosgene, some difficulties, especially in the formation of [(11)C]phosgene process from [(11)C]CCl(4), hamper its use. The present article shows a simple preparation method for [(11)C]phosgene. [(11)C]CCl(4) was obtained using the conventional method by passing a mixture of [(11)C]CH(4) and Cl(2) through a heated quartz tube. The [(11)C]CCl(4) was transformed to [(11)C]phosgene simply by passing through a pretreatment tube of a Kitagawa gas detection system for the working-environmental CCl(4) concentration measurement at room temperature with a flow rate of 50 ml/min. This tube successfully transformed [(11)C]CCl(4) to [(11)C]phosgene at room temperature. [(11)C]Phosgene was obtained at nearly 80% radiochemical yield (EOB) in a short synthesis time with high reproducibility. A high yield and reliable [(11)C]phosgene production method using a gas detector tube system for working-environmental CCl(4) concentration measurement was developed.