Application of DPASV to the study of heavy metal complexation in colloidal latex dispersions

Differential pulse anodic stripping voltammetry (DPASV) was applied to the study of the binding of Zn-II, Cd-II and Pb-II by two kinds of polystyrene latex particles at different pH values and at different electrolyte concentrations. For the calculation of stability constants, the criterion of consistency between current and potential data was applied. For Cd-II and Pb-II, the application of DPASV yields qualitatively good results (in agreement with those previously found by DPP). However, from a quantitative point of view, the consistency criterion often reduces the applicability of the technique to quite narrow pH ranges, which increases the error in some calculations. In the case of Zn-II certain anomalies were found, rendering quantitative considerations impossible.