Potentiometric detection of anions separated by liquid chromatography using a metallic silver wire electrode

A silver metallic wire electrode, coated with AgCl, used for potentiometric detection of inorganic anions in liquid chromatography, is described. The electrode response to the anions was evaluated by both static and flow injection measurements, and results have shown that the electrode exhibits sensitive response to Cl- and SCN- with a detection limit of 10-6 M. The electrode was used as a potentiometric detector for the determination of anions following separation by ion chromatography using the eluent containing 5 mM phthalate at pH 4.2. Calibration plots were not linear, but give a useful working range of 5 ×10-5 to 3 × 10-2 M. It also demonstrated to be a useful detector for the detection of anions separated, where the separation of anions was preformed with a C18 column using a 0.1 mM octylammonium salicylate as an ion-paring reagent, by ion-pair chromatography. The determination of chloride in waste water samples were demonstrated by proposed method.