Arno De Klerk and Cornelius J. Rademeyer
The effect of sodium on the determination of Au, Ir, Pd, Pt, Rh and Ru was studied. It was found that emission intensities were suppressed by sodium concentrations above 0.02 mol dm–3 and that this effect was enhanced by increasing acid concentration. Detection limits could be improved by sodium addition, with the highest sensitivity found at 0.01 mol dm–3, while no adverse effects on precision were observed. Sodium had no apparent effect on the excitation temperature or electron density of the plasma.