Effectiveness of palladium chemical modification for the determination of cadmium by graphite furnace atomic absorption spectrometry

The effect of palladium on the cadmium absorbance signal was investigated. To reduce the background absorbance due to sodium chloride, large amounts of palladium should be avoided. A combination of 6 µg of palladium and 500 µg of ammonium nitrate allows the direct determination of cadmium in undiluted urine against aqueous standards. The detection limit (3σ) was calculated to be 0.1 µg l–1. This mixed modifier is shown also to be applicable to the analysis of milk and blood with a detection limit of 0.5 µg l–1.