A Rapid Sequential Separation of Actinides in Bioassay Samples Using Extraction Chromatography and Vacuum Assisted Flow

Anil Thakkar

Eichrom Technologies, Inc., Thakkar@eichrom.com

In order to address the continuing need for faster radioanalytical methods Eichrom has developed a new configuration for its existing extraction chromatographic material that operates with vacuum assisted flow. In this paper, a scheme for separation of actinides in bioassay samples will be discussed using Eichrom Resin Cartridges. Time required for separations, test results and ease of use will be the primary discussion of this paper.

Actinides from 1.2 L of urine sample are preconcentrated using a calcium phosphate precipitation. Fecal samples are ashed and then digested with nitric acid, hydrochloric acid and hydrofluoric acid. Finally, samples are dissolved in

3M HNO₃/1M Al(NO₃)₃ solution. Actinides are separated using Eichrom UTEVA and TRU Resin Cartridges. The cartridges are placed in tandem on a vacuum box system. Sample solutions are then passed through the cartridges under optimal vacuum pressure. Uranium is eluted from UTEVA Resin with 0.01M hydrochloric acid, and Am and Pu are eluted from TRU Resin with 9M and 4M hydrochloric acid, and with 0.01M ammonium bioxalate respectively. A cerium fluoride precipitation is carried out and samples are counted via alpha spectrometry.

An average recovery for Am of 75%, an average recovery for Pu of 94% and an average recovery for U of 82% are obtained using this method. Results obtained from this work indicate that Eichrom Resin Cartridges provides fast and effective means to separate actinides in bioassay samples.