Development of a fast and efficient analytical technique for the isotopic analysis of fission and actinide elements in environmental matrices.

An automated separation-direct analysis scheme has been developed to determine both the concentration and isotopic composition of a suite of elements down to the low picogram level in a complex silicon-based matrix. With the ultimate goal of performing rapid analysis of materials with non-natural isotopic compositions, RAPID (Rapid Analysis of Post-Irradiation Debris) consists of a high-pressure ion chromatography system directly coupled to an inductively coupled plasma mass spectrometer. The RAPID method achieves matrix exclusion and direct online analysis of the elementally separated components, yielding precise isotopic compositions for up to 40 elements in less than one hour per sample. When combined with isotope dilution, this approach shows the potential to yield elemental concentrations with low uncertainties, providing a rapid analytical method that encompasses group I and II metals, transition metals, refractory metals, platinum group metals, lanthanides, and actinides. The method development, robustness, sensitivity, uncertainties, and potential applications in nuclear and environmental measurements will be discussed in this paper.