APPLICABILITY OF CHEMICALLY-MODIFIED ELECTRODES FOR DETERMINATION OF COPPER SPECIES IN NATURAL-WATERS

A procedure based on the stripping voltammetric determination of labil e copper after its chemical accumulation on a graphite electrode modif ied with a complexation agent and a Nafion film is described. The meth od is sufficiently sensitive for the copper determination in the nM to mu M range with a relative standard deviation of 1 to 6%. The detecti on window of the proposed technique is similar to that of conventional differential pulse polarography. Results for the copper speciation an d the copper complexation capacity in model samples and in river water s are presented. A mathematical description of competitive complexatio n equilibria is discussed.