Quality assurance for PET gas production using the Cyclone 3D oxygen-15 generator

The production and quality control analysis of short-lived (t1/2=2.03 min) oxygen-15 labelled gases ([15O]O2, [15O]CO, and [15O]CO2) from a Cyclone 3D accelerator for positron emission tomography (PET) in human subjects has been established and evaluated on a routine basis use at the MRC Cyclotron Unit and are here described. Contaminant levels have been identified and measured by radio-gas chromatography. The maximum levels allowed, measured as a percentage of total delivered activity (v/v), are 3.7% for total nitrogen oxides and 1% for [15O]CO in [15O]CO2 and [15O]CO2 in [15O]CO. By adjunction of a cryogenic or molecular sieve trap, radiopharmaceutical gases are routinely produced well within these specifications.