Determination of silver(I) ion in water samples by graphite furnace atomic absorption spectrometry after preconcentration with dispersive liquid-liquid microextraction

A method was developed for the determination of silver ion (Ag) by combining dispersive liquid-liquid microextraction preconcentration with graphite furnace atomic absorption spectrometry. Diethyldithiocarbamate was used as a chelating agent, and carbon tetrachloride and methanol as extraction and dispersive solvent. Factors influencing the extraction efficiency of Ag and its subsequent determination were studied and optimized. The detection limit is 12 ng L-1 (3 s) with an enrichment factor of 132, and the relative standard deviation is 3.5% (n = 7, at 1.0 ng mL(-1)). The method was successfully applied to the determination of trace amounts of Ag in water samples.