Ion chromatographic separation and determination of phosphate and arsenate in water and hair

A simple and sensitive method for the sequential determination of phosphate and arsenate was developed based on initial ion chromatographic separation followed by detection as the ion-association complex formed by heteropolymolybdophosphate and arsenate with bismuth. With 200 μl sample injection and separation on a AS4A-SC column using an eluent of 3.5 mM sodium hydrogen carbonate–10.0 mM sodium hydroxide, the detection limits which are calculated as the concentration equivalent to twice the baseline noise, were found to be 0.8 μg/l and 4.2 μg/l for P and As, respectively. Spiked samples were analyzed and recoveries were found to be satisfactory in the range of 95–105% for phosphate and 90–105% for arsenate. Samples of water and hair were analyzed by the proposed method.