Estimation of239Pu in urine, influence of Sulkowich reagent

Plutonium is known to be co-precipitated with Sulkowich reagent as calcium ammonium oxalate. In adopting this technique for bio-assay of plutonium, its accuracy depends on the self-absorption of the resulting precipitate in each urine sample. Pu recovery experiments were carried out with varying concentration of Ca and Mg, using different volumes of Sulkowich reagent. When the sample volume is 500 ml, Pu in urine can be estimated with an accuracy and precision of 74.38%±7.4%; with a detection limit of 0.06 Bq (1.6 pCi) per dm3. An attempt was made to improve the detection limit, accuracy and precision values. The results obtained are presented in this paper.