Sequential Isotopic Determination of
Strontium, Thorium, Plutonium, Uranium,
and Americium in Bioassay Samples

Y. K. Lee, S. N. Bakhtiar, M. Akbarzadeh, J. S. Lee

A procedure is presented to provide sequential determination of isotopic strontium, thorium, uranium, and americium in a single biological sample. The method begins with digestion and dissolution of the sample. Tracers and /or carriers are added to the sample for the purpose of chemical yield monitoring. Strontium is first separated
from the actinides and from most of the interfering constituents of
the sample by precipitation as carbonates. Strontium isotopes are purified, and Sr- 89 and Sr - 90 are measured by gas proportional counting. Actinides are separated and purified by ion exchange
chromatography, co-precipitated with neodymium fluoride, filtered,
and counted by alpha-particle spectrometry.

Published in Journal of Radioanalytical and Nuclear Chemistry,
Vol. 243, No. 2 (2000) 525-533