Palladium as a chemical modifier for the determination of lead in food slurries by electrothermal atomisation atomic absorption spectrometry

Abstract

Palladium is shown to be superior to ammonium dihydrogen phosphate as a modifier for lead in the analysis of food slurries by electrothermal atomisation atomic absorption spectrometry. A conventional autosampler was modified to permit magnetic stirring of the slurry samples in the autosampler cups. Stirred slurries can be accurately and precisely pipetted into a graphite furnace up to concentrations of 5%m/V. Above this, systematic errors occur. A method is described for the determination of lead in slurries up to a concentration of 4%m/V. The procedure involves calibration with aqueous standards, palladium matrix modification and platform atomisation.