A fast method for the determination of residual solvents in 18FDG and 11C-methionine samples

A method for the determination of residual solvents in the commonly used radiopharmaceuticals 18F-fluorodeoxyglucose (18F-FDG) and 11C-methionine is proposed. This method is applicable to formulations even with high ethanol content up to 10% and offers a low detection limit: 3 mg/L for methanol, 3 mg/L for ethanol and 0.4 mg/L for acetonitrile. Other advantages include short sample preparation and chromatographic separation times and minimum manual operation. To test the performance of the method 18F-FDG and 11C-methionine were synthesized in a number of consecutive runs and the residual solvent content was checked.