Sequential Separation of Strontium-90, Yttrium-90, Promethium-147, and Cerium-144 from Urine and Their Subsequent Estimation

摘要

A method has been developed for separating low-level activities of the beta-emitting isotopes strontium-90, yttrium-90, promethium-147 and cerium-144 from urine and aqueous solutions. They are subsequently estimated by planchet or liquid scintillation counting. The radionuclides are separated from each other and from interfering elements by solvent extraction with HDEHP (di-2-ethylhexyl phosphoric acid) in n-heptane. It is possible to separate the elements with a minimum of cross-contamination by selecting appropriate pH's and solvent concentrations. Percentage recoveries for the radionuclides are: exp 90 Sr, 100 +- 12; exp 90 Y, 65 +- 4; exp 147 Pm, 90 +- 8; exp 144 Ce, 87 +- 11. The limits of detection are: exp 90 Sr, 0.6 pCi; exp 90 Y, 0.7 pCi; exp 147 Pm, 1.0 pCi; exp 144 Ce, 0.8 pCi. (Atomindex citation 12:631717)