ADSORPTIVE CATHODIC STRIPPING VOLTAMMETRIC DETERMINATION OF ANTIMONY IN THE PRESENCE OF COPPER AND BISMUTH BY USING HEMATOXYLIN

This study describes a new adsorptive cathodic stripping voltammetric method using hematoxylin as complexing reagent for determination of antimony in the presence of Cu(II) and Bi(III). The method is based on the accumulation of Sb(III)-hematoxylin complex onto a hanging mercury drop electrode (HMDE), and reduction of the antimony in the adsorbed complex by using square wave cathodic stripping voltammetry. The effects of chemical (pH, supporting electrolyte, concentration of hematoxylin) and instrumental (accumulation potential, accumulation time,. stripping mode and scan rate) parameters on the measured current as response are discussed. The linear relationship was obtained in the concentration range of 2.7-80 mu g L-1 (r = 0.998, n = 10). The detection (3s) and the quantification (10s) limits were estimated to be 0.8 mu g L-1 and 2.7 ug L-1, respectively. The method was applied to determination of Sb(III) in water samples.