Determination of manganese by graphite furnace atomic absorption spectrometry: matrix effect control by multiple linear regression model

The multivariate interference effects due to nitrates of sodium, potassium, magnesium and calcium on electrothermal atomization of manganese were modelled by using the multiple linear regression method in conjunction with a suitable experimental design. Since the model proved to be able to efficiently predict the simultaneous effects of the considered salts in a wide range of concentrations, it was applied to provide a computational correction of the matrix effects occurring in the ETAAS analysis of manganese in seawater, after preconcentration of the analyte on Chelex-100 resin and elution with nitric acid. Preliminary results showed that the matrix effects are significantly reduced, leading to an improvement in accuracy of the ETAAS analysis. (C) 1999 Elsevier Science B.V. All rights reserved.