Anti-fouling In situ Deposited Antimony/Nafion Film Electrode for Electrochemical Stripping Analysis

摘要

An antimony film electrode for anodic stripping voltammetric analysis in complex solution wasinvestigated, with lead and cadmium employed as test metal ions. Ascorbic acid or dopamine, whichexist in most mammals and their metabolites in relatively high concentrations, interfere with thedetermination of metal ions by electrochemical stripping analysis. The influence of ascorbic acid anddopamine on the stripping voltammetric response of antimony film electrodes was evaluated. Theadsorption of these biomolecules onto the electrode caused decreased and non-distinguishablestripping peaks. The interference of the biomolecules on antimony stripping electrodes can beovercome by Nafion pre-coating. In situ deposited antimony/Nafion-coated glassy carbon electrodesexhibited higher sensitivity for electrochemical stripping analysis of cadmium and lead with limit ofdetection approximately 0.015 g L-1 in the presence of ascorbic acid or dopamine. The effective anti- fouling capability to ascorbic acid or dopamine makes the in situ deposited antimony/Nafion-coatedelectrode very attractive for direct measurements of trace metals in complex media.