Coprecipitation of ruthenium with chitosan and its determination by graphite furnace atomic absorption spectrometry Original Research Article

A coprecipitation method with chitosan was studied for the determination of ruthenium in water samples by graphite furnace atomic absorption spectrometry. Ruthenium (0.1–5.0 μg) is coprecipitated quantitatively from a aqueous sample solution (100–1000 cm3) with chitosan at pH 7.5–8.5. After the coprecipitate was separated by centrifuging from the aqueous sample solution, it was dissolved in 1.0 cm3 of 1.0 mol dm−3acetic acid and diluted to 5.0 cm3 with water. An aliquot of the resulting solution was injected into the graphite furnace. The calibration graph by the proposed method was linear up to 5.0 μg dm−3, and the detection limit (S/N = 3) for ruthenium was 0.06 μg dm−3. The relative standard deviation at 1.0 μg dm−3 was 3.0–4.0% (n = 5). The proposed method was applied to the determination of trace amounts of ruthenium in water samples.