Triple-phase single-drop microextraction of silver and its determination using graphite-furnace atomic-absorption spectrometry.

A new method is described for the determination of silver based on triple-phase microextraction using diethyldithio-carbamate (DDTC) and thioaminophenol. Ag is separated and preconcentrated from the matrix of the sample solution, and finally determined by electrothermal atomic-absorption spectroscopy. The parameters that affect the efficiency were investigated. Under the optimized conditions, a 30-fold preconcentration factor with a detection limit of 0.05 microg L(-1) was achieved. The relative standard deviation was 10% (5 determinations). The developed method was applied to the determination of trace Ag in water samples.