MICROI\NALVTICI\L INVESTIGI\TIONS FOR THE ASSESSMENT OF TRAGE METAL CONCENTRATIONS OV ION CIIROMI\TOGRAPIIV AND ATOMK SPECTROSCOPY

Abstract

Many new analytical techniques have been introduced as free from interferences , however, when applied to routine analysis and systematic determination few of these claims have survived intact.

In atomic absorption spectrometric study, it was found that, most carefulness must be spent to the optimization of the analytical tool to overcome the direct effect of matrix on the analyte determination. A typical examples for a significant contribution to matrix effect are the arsenic with sodium and potassium phosphate, cadmium with magnesium and calcium sulfate, lead with aluminum and magnesium nitrate, antimony with phosphorus and antimony with iron nitrate, selenium with sodium sulfate and phosphate, and thallium with sodium and potassium chloride. Therefore it must be taken in consideration the type of analytical analyte as. well as the chemical composition and concentration of the interfering matrix.

The detection limit for all the studied analytes is much

better for GFAAS than the corresponding value in ICP-ES. Therefore it is not allowed to generalize or to extrapolate into the extreme trace level in any way. Each solution of an analytical problem needs its individual strategy.

Most carefulness must be taken to the problem (a) formation of refractory stable complex and (b) volatilization effect of the element which causes a significant suppression and hence negative errors.