A cloud-point extraction process using micellar medium has been investigated for the spectrophotometric
determination of Ag(I) in real samples. The proposed method was based on the selective reaction between
silver ions and an azo dye reagent, 5-(40-chlorophenylazo)-6-hydroxypyrimidine-2,4-dione (CPAHPD), in
the presence of cetyltrimethylammonium bromide (CTAB) and potassium iodide salt at pH 5.5. The
optimal reaction conditions were studied and the analytical characteristics of the method were obtained.
Linearity for Ag(I) concentration was obeyed in the range of 0.3–5.0 ng mL1. The molar absorptivity was
calculated to be 1.55 107 L mol1 cm1 at 666 nm, while the Sandell sensitivity value was found to be
0.007 ng cm2. The detection and quantification limits were 0.095 and 0.297 ng mL1, respectively. The
interference effects of different anions and cations were also examined. The proposed method was
successfully used to determine Ag(I) in sulphargin, radiological films, panchromatic plates, human hair,
tea and water samples. |