Ewa Stryjewska

Speciation of Arsenic(V) and Arsenic(III) in Soil Extracts by Cathodic Stripping Voltammetry

Cathodic stripping voltammetry with a hanging mercury drop electrode was applied for the determination of As(III) and As(V) in soil extracts. The content of inorganic arsenic(III) and arsenic(V) compounds was determined after chemical reduction of arsenic(V) by KI and ascorbic acid solution, while arsenic(III) was determined in the solution without the reduction. Organic compounds were determined after UV irradiation of the samples. For arsenic compounds extraction three different extractants were tested: water/methanol, ortophosphoric acid and mixture of HCl/HNO3. As different arsenic forms have different toxicity, the ability to discriminate between them is a distinct advantage of the proposed method.

Adsorptive voltammetry for the determination of trace amounts of aluminium in blood serum derived products

A method for the determination of aluminium in blood serum derived products is described. The samples are mineralized in an open system with a mixture of nitric and perchloric acids, followed by H2O2 addition. The determinations are carried out by adsorptive stripping voltammetry with calmagite in acetate buffer.

Statistical estimation of the influence of mineralization methods on the results of heavy metals determination in cereals by the DPASV method

SummaryThe elements Cd, Cu, Pb and Zn have been determined in wheat, barley and oats by differential pulse anodic stripping voltammetry after wet mineralization, mineralization by dry ashing or mineralization in a PTFE bomb. The procedures are described. The results were evaluated by BASIC programs for one dimensional data evaluation, by principal components plot and by multidimensional analysis of variance. The influences of mineralization procedures on the results are low compared with the different contents in the three cereals particularly for Cd, but also for Pb and Zn. There are no significant differences, in the Cu content.