Extrapolation to infinite dilution: a method for overcoming matrix effects

Abstract

A method is proposed for the correction of matrix effects by successive dilution of the test solution with measurement of the analyte at each stage. The raw results are extrapolated to zero concentration (or infinite dilution), at which point the hypothetical matrix is pure solvent. This provides an unbiased estimate of concentration without the need for a matrix matched calibration set. The method has been shown to work well for inductively coupled plasma atomic emission spectrometry and atomic absorption spectrometry. Strategies for implementing the method as an automatic adjunct to modern instruments are discussed.