A method for the separation and determination of total and isotopic uranium and plutonium by ICP/MS was developed for IAEA
samples on cellulose-based media. Preparation of the IAEA samples involved a series of redox chemistries and separations using
TRU® resin (Eichrom). The sample introduction system, an APEX nebulizer (Elemental Scientific, Inc.), provided enhanced nebulization
for a several-fold increase in sensitivity and reduction in background. Application of mass bias (ALPHA) correction factors
greatly improved the precision of the data. By combining the enhancements of chemical separation, instrumentation and data
processing, detection levels for uranium and plutonium approached high attogram levels.