Analytical Sciences


Abstract − Analytical Sciences, 15(9), 851 (1999).

Determination of Ultratrace Amounts of Osmium Using Catalytic Wave of OsO4-Bromate System by Voltammetric Method
Ali A. ENSAFI * and K. ZAREI
College of Chemistry, Isfahan University of Technology, Isfahan, Iran
Highly sensitive catalytic waves of OsO4-bromate linear sweep voltammetric and square wave voltammetric techniques were proposed for the determination of ultratrace amounts of osmium. Under optimized conditions, the catalytic linear sweep voltammetric procedure gives excellent reproducibility and limits of detection and a linear dynamic range and gives a low signal for background, whereas the square wave voltammetric technique gives higher sensitivity, but the background signal was high and the linear dynamic range was narrower. The methods are suitable for the determination of osmium as osmium tetroxide as low as 1.5x10-10 mol/l. The currents are linear for the concentration ranges of 0.10 - 210.0 ng/ml and 0.20 - 2.0 ng/ml for linear sweep voltammetry and square wave voltammetry, respectively. (Keywords: Osmium, bromate, voltammetry)