Standardization of 64Cu activity

Published

May 25, 2018

Author(s)

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

Abstract

The complex decay scheme that makes 64Cu promising as both an imaging and therapeutic agent in medicine also makes the absolute measurement of its activity challenging. The National Institute of Standards and Technology (NIST) has completed a primary activity standardization of a 64CuCl2 solution using the 4πβ(LS)-γ(NaI) live-timed anticoincidence (LTAC) counting method. Two liquid scintillation (LS) counting methods were employed for confirmatory measurements. Secondary measurements were made by high-purity germanium detectors, pressurized ionization chambers (IC), and a well-type NaI(Tl) counter. Agreement between the LTAC-based standard and standards from other laboratories was established via IC calibration factors. Poor agreement between methods and with theoretical IC responses may indicate a need for improved β+/- branching probabilities and a better treatment of β+/- spectra.

Citation

Applied Radiation and Isotopes

Volume

139

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.apradiso.2018.05.023

Keywords

Copper-64, beta-gamma coincidence method, anticoincidence, liquid scintillation, triple-to- double coincidence ratio, TDCR, efficiency tracing, Monte Carlo, ionization chamber, nuclear decay data

Citation

Bergeron, D. , Cessna, J. , Fitzgerald, R. , Pibida, L. and Zimmerman, B. (2018), Standardization of 64Cu activity, Applied Radiation and Isotopes, [online], https://doi.org/10.1016/j.apradiso.2018.05.023 (Accessed December 26, 2024)