Polypyrrole coated mercury film electrodes for sono-ASV analysis of cadmium and lead

The feasibility of using reduced polypyrrole (PP), poly(acenaphtho[1,2-c]pyrrole) (PANP), and poly(4,9-dihydro-o-benzenonaphtho[2,3-c]pyrrole) (PDBNP) coated mercury thin film glassy carbon electrodes for the anodic stripping voltammetric determination of cadmium and lead in the presence of ultrasound is examined. The magnitude of the stripping peak for a given solution of cadmium and lead in 0.1 M acetate buffer at the polymer coated electrodes was found to follow the order of PDBNP > PANP > PP. This is rationalized in terms of the structure of the polymer chains. The influence of surfactants on the stripping response was investigated. Four types of surfactant were examined: sodium dodecyl sulfate (SDS), Triton X-100 (TX), bovine serum albumin (BSA), and dodecyl pyridinium chloride (DPC). While each was found to have a deleterious effect on peak height, it was found that the PDBNP coated electrode performed well in the presence of SDS solution. The three mercury film glassy carbon electrodes were found to be mechanically resistant under sonication as shown by atomic force microscopy (AFM).