Radioactivity measurements for diagnostic and therapeutic nuclear medicine in the United States are based on measurements at NIST. Activity measurements for γ-ray-emitting radionuclides are made using 4πγ ionization chambers calibrated against primary standards developed in the Radioactivity Group. Primary standards of α- and β-emitting radionuclides are typically developed using 4πβ liquid scintillation spectrometry and 4πβ-γ anticoincidence counting. The calibration process also includes the identification and quantification of radionuclidic impurities by high-purity germanium γ-ray spectrometry. Recent development work has focused on therapeutic nuclides for nuclear medicine, radioimmunotherapy, bone palliation, and diagnostic imaging. The current focus of our work is on the development of standards and measurement tools for α-emitters used in Targeted Alpha Therapy and in the development of quantitative tools for preclinical imaging.
The radiopharmaceutical standardization laboratory provides calibration services for radionuclides and is available for technical users who must make measurements consistent with national standards or who require higher accuracy calibrations than are available with commercial standards. NIST also undertakes basic research to develop new methods of standardizing radionuclides for diagnostic and therapeutic applications. These studies include measurements of decay-scheme parameters, such as half-lives and γ-ray emission probabilities, and identification of radionuclidic impurities.
The customer has no direct access to the facility. NIST staff can provide calibration services for any previously standardized radionuclide through the Radioactivity Group’s measurement services. Research to develop standards for previously unstandardized radionuclides can be undertaken on a cost-recovery basis.