DETERMINATION OF TRACES OF ARSENIC(III) BY ANODIC-STRIPPING VOLTAMMETRY IN SOLUTIONS, NATURAL-WATERS AND BIOLOGICAL-MATERIAL

The determination of arsenic(III) in aqueous solutions by differential pulse anodic stripping voltammetry using disc gold electrode is descr ibed. Linear calibration curves were obtained in the concentration ran ge between 0.2 and 250 mu g 1(-1) of arsenic, the detection limit was 0.15 mu g1(-1). Good reproducibility of measurements is achieved by a programmed electrochemical treatment of the electrode surface before e ach measurement. The shift of the potential of anodic dissolution peak of arsenic caused by adsorption of surface active substances is discu ssed. The method can be applied for analysis of various types of natur al waters. For the analysis of materials of complex composition the me thod of automatic exchange of supporting electrolyte is described. (C) 1998 Elsevier Science B.V. All rights reserved.