Imidazole modified C-paste electrode in the determination of trace amounts of Mercury

Abstract

The imidazole-modified C-paste electrode was shown lo accumulate mercury (II) ions non- electrochemically from nitrate containing solutions at pH 7.0-7.3. The accumulated mercury gave well defined voltammograms, when subjected to voltammetric scale in a medium of potassium thiocyanate and perchloric acid; these are suitable for determination of mercury. In comparison with pure C-paste electrodes, the imidazole-CME is shown to offer improved resistance to interference by diverse types of ions present in natural waters. The method offered a sensitivity of 1.75 μA/ppm and a detection limit of 0.1 ppm (lor 15 min. accumulation time). The relative standard deviation was 12%.