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Long-term stability of carrier-added Ge-68 standardized solutions



Brian E. Zimmerman, Denis E. Bergeron, Ryan P. Fitzgerald, Jeffrey T. Cessna


Tests for chemical stability were carried out on carrier-added 68Ge solutions prepared and calibrated in 2007 and 2011 to evaluate the suitability of the specific composition as a potential Standard Reference Material. Massic count rates of the stored solutions were measured using a NaI(Tl) well counter before and after gravimetric transfers. The present activity concentration of the 2007 solution was also measured using live-timed anticoincidence counting (LTAC) and compared to the 2007 calibrated value. The well counter data indicated no change in massic count rate to within uncertainties for either solution. The LTAC measurements gave a difference of -0.49 % in the activity concentration 2007 solution over 7 years. However, the uncertainty in the decay correction over that time, due to the uncertainty in the 68Ge half-life, accounted for the majority (0.67 % out of 0.83 %) of the standard uncertainty on the activity concentration. The results indicate that these carrier-added solutions are stable with regard to potential activity losses over several half lives of 68Ge.
Applied Radiation and Isotopes


Germanium-68, solution stability, reference materials


Zimmerman, B. , Bergeron, D. , Fitzgerald, R. and Cessna, J. (2016), Long-term stability of carrier-added Ge-68 standardized solutions, Applied Radiation and Isotopes, [online], (Accessed June 16, 2024)


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Created March 1, 2016, Updated February 19, 2017