ELIMINATION OF INTERFERENCE EFFECTS BY STANDARD ADDITION AND SUCCESSIVE DILUTION METHOD IN THE GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY

The effectiveness of the standard addition and successive dilution (SA SD) method for evaluation of analytical signals measured by graphite f urnace atomic absorption spectrometry was tested. The investigations w ere carried out on the basis of determination methods for cadmium, ars enic, and lead by using palladium or mixed palladium-magnesium modifie r in the presence of chloride ions as interferents. In all these cases the mechanism of interference processes has a complex character and p alladium modifier participates in it. It was found that SASD method ma y be successfully applied to achieve the correct analytical results ev en in such cases when the interference effect is so complex as in the analytical methods being considered in this paper. However, sometimes the repetition of the determination in the presence of two different b uffer interferents is necessary.