Precision and accuracy attainable with isotope dilution analysis applied to inductively coupled plasma mass spectrometry: theory and experiments

Abstract
The use of isotope dilution analysis (IDA) in combination with inductively coupled plasma mass spectrometry (ICP-MS) is discussed. In particular, theoretical calculations are presented on the precision and accuracy attainable in the relatively high elemental concentration range. The results of these calculations have been applied to the determination of the amount of Re and Pt on two types of catalysts, with the intention of validating high-precision wet-chemical analysis methods developed for these systems. Both for Re and for Pt the results of the IDA using ICP-MS and the wet-chemical methods were in excellent agreement. Furthermore, for Pt, different amounts of spike material were used to investigate whether the calculations correlate with the experimental data. The results show the value of the theory in predicting the precision and accuracy attainable for a specified amount of spike material.