Isotopic dilution analysis using ICP/AES: application to uranium samples and comparison to MC ICP/MS measurements

An ICP/AES owning a high resolving power is able to measure the isotopic shift in emission atomic lines for heavy elements such as uranium. 235U and 238U are therefore clearly separated and identified. Using this phenomenon, the transposition of isotopic dilution mass spectrometry method to the ICP/AES instrument allows to quantify, with accuracy and precision, the 235U content of a solution. The method, named IDAES, is the first that combine isotope dilution method and ICP/AES measurements. In order to demonstrate the validity of the IDAES method, an IDMS protocol using a MC ICP/MS instrument, is also applied to determine the amount content of 235U of the sample.