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Improving the NIST High-Performance ICP-OES Methodology through Exact Matching



Michael R. Winchester, Therese A. Butler, Gregory C. Turk


High-Performance” (HP-)ICP-OES was developed at the National Institute of Standards and Technology (NIST) approximately a decade ago as a means of performing ICP OES analyses with relative expanded uncertainty on the order of 0.2 %, expressed at a level of confidence of 95 %. The technique was developed under the assumption that ICP-OES is sufficiently immune to matrix effects and instrument response nonlinearity to obviate the need for very careful matching of calibration solutions to unknown sample solutions. However, through long experience, NIST has learned that HP-ICP-OES can often be improved by exactly matching the analyte mass fractions, internal standard mass fractions, and matrix compositions among the solutions prepared for an analysis. When properly implemented, exact matching enables the relative expanded uncertainties associated with HP-ICP-OES analysis to be improved by a factor of two to approximately 0.1 %.
Analytical Chemistry


accuracy, easily ionized element, exact matching, inductively coupled plasma optical emission spectrometry, matrix effects, metrological uncertainty, nonlinearity


Winchester, M. , Butler, T. and Turk, G. (2010), Improving the NIST High-Performance ICP-OES Methodology through Exact Matching, Analytical Chemistry, [online], (Accessed May 30, 2024)


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Created August 26, 2010, Updated November 10, 2018