Mvr. Prasad et al., SEQUENTIAL ESTIMATION OF RU-106, CS-137, AND SR-90 IN URINE, Journal of radioanalytical and nuclear chemistry, 197(2), 1995, pp. 281-293
A sequential method has bren developed for the estimation of Ru-106, C
s-137 and Sr-90 in urine using beta counting. After completely destroy
ing the organic matter in urine, Ru-106 is oxidized to volatile ruthen
ium tetroxide and allowed to react in-situ with polyethylene powder; C
s-137 is concentrated on ammonium phosphomolybdate and estimated as te
traphenylborate; Sr-90 is coprecipitated as strontium sulphate and con
verted to carbonate. The recoveries have been found to be better than
83% for all of the radionuclides. The minimum detection limits are 0.1
6, 0.85, and 0.14 Bq/dm(3) for Ru-106, Cs-137, and Sr-90, respectively
. Yttrium-90 fraction of Sr-90 is also estimated using sodium nitropru
sside as reagent, after allowing it to grow for 14 days.