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In this work, we describe a new and promising type of selenium film electrode for anodic stripping voltammetry. This method is based on formation of copper selenide onto an in-situ formed selenium-film carbon electrode, this followed by Osteryoung square-wave anodic stripping voltammetry. Copper(II) is also in-situ electroplated in a test solution containing 0.01 mol L-1 hydrochloric acid, 0.05 mol L-1 potassium chloride and 500 µg L-1 Se(IV) at a deposition potential of −300 mV. Well-defined anodic peak current observed at about 200 mV is directly proportional to the Cu(II) concentration over the range of 1.0─100 µg L-1 under the optimized conditions. The detection limit (3 sigma level) is 0.2 µg L-1 Cu(II) at 180 s deposition time. Relatively less interferences are shown from most of metal ions except for antimony(III). The proposed method can be applied to sample analyses of river water and oyster tissue with good accuracy.

A selective and simple method is presented for the determination of Pb(II) by constant current stripping chronopotentiometric analysis (CCSCP) using bismuth film electrode. This method is based on the extraction of the bromide complex into propylene carbonate, followed by CCSCP measurements in the organic phase. CCSCP studies revealed that Pb(II) gave a characteristic response at about À 0.52 V vs. Ag/AgCl on the stripping chronopotentiogram (dt/dE curve) after recording a potential vs. time curve at 3.0 mA. The peak height of Pb(II) response was directly proportional to the initial metal concentration of the aqueous phase in the ranges of 1.0 -22.0 mg dm À3(correlation coefficient 0.997) when the optimized parameters were used. A detection limit (S/N ¼ 3) of 0.0880 mg dm À3 Pb(II) was obtained at 180 s deposition time. The relative standard deviation was 3.2% on replicate runs (n ¼ 12) for the determination of 10.0 mg dm À3 Pb(II). Analysis of certified reference materials has confirmed the applicability of the proposed method for determination of Pb(II) in soil and water samples.