Nernst-Planck-Poisson Model for the Description of Behaviour of Solid-Contact Ion-Selective Electrodes at Low Analyte Concentration

Abstract

All-solid-state electrodes are increasingly being used in clinical, industrial and environmental analysis. This wide range of applications requires deep theoretical description of such electrodes. This work concentrates on the development of a numerical tool for the qualitative prediction of electrochemical behaviour for solid-contact ion-selective electrodes at low analyte concentrations. For this purpose, a general approach to the description of electro-diffusion processes, namely the Nernst-Planck-Poisson (NPP) model, was applied. The results obtained from this model are verified by experimental data of lead(II)-selective electrodes based on a polymeric PVC membrane with polybenzopyrene doped with Eriochrome Black T used as the solid contact.