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Standardization of I-124 by three liquid scintillation-based methods.

ABSTRACT: A solution of ¹²⁴I was standardized for activity by 4??(LS)-?(NaI) live-timed anticoincidence (LTAC) counting, with confirmatory measurements by triple-to-double coincidence ratio (TDCR) and CIEMAT-NIST efficiency tracing (CNET) liquid scintillation counting. The LTAC-based standard was shown to be in agreement (within k?=?1 uncertainties) with previous measurements at NIST and elsewhere. Calibration settings for radionuclide calibrators were determined and a discrepancy with literature values, partially due to a calibration methodology dependent upon an erroneous setting for ¹⁸F, was identified and explained.

SUBMITTER: Bergeron DE

PROVIDER: S-EPMC6839768 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Standardization of I-124 by three liquid scintillation-based methods.

Bergeron D E DE Cessna J T JT Fitzgerald R R Pibida L L Zimmerman B E BE

Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine 20190809

A solution of <sup>124</sup>I was standardized for activity by 4πβ(LS)-γ(NaI) live-timed anticoincidence (LTAC) counting, with confirmatory measurements by triple-to-double coincidence ratio (TDCR) and CIEMAT-NIST efficiency tracing (CNET) liquid scintillation counting. The LTAC-based standard was shown to be in agreement (within k = 1 uncertainties) with previous measurements at NIST and elsewhere. Calibration settings for radionuclide calibrators were determined and a discrepancy with literatu ...[more]

PMID: 31465950

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