Long-lived radionuclidic impurities in the production of ¹⁸F-labelled radiopharmaceuticals

Long-lived radionuclides with half-lives from 5 to 312 days are common radionuclide impurities in ¹⁸F-labelled radiopharmaceuticals. They are produced along with [¹⁸F]fluoride under the action of high-energy protons, neutron and γ-quants on target body and ion window foil during irradiation of [¹⁸O]H2O. Subsequent elution of the impurities to a synthesis module results in the contamination of radiopharmaceutical products, as well as radioactive waste accumulation. In the present study the isotopic composition and partition of long-lived radionuclides between recovered [¹⁸O]H2O, solid state extraction cartridges, as well as the final pharmaceutical preparations were studied by means of HPGe γ-spectrometry and liquid scintillation technique.