Application Of Bismuth-film Modified Glassy Carbon Electrode For Solid-phase Extraction Of Sudan I

A sensitive electrochemical sensor for detection of sudan was developed based on solid-phase extraction (SPE) at bismuth-film modified glassy carbon electrode. SPE of sudan may be due to the physical adsorption between sudan and the bismuth film. The properties of the bismuth-film electrode (BiFE) designed for detection Sudan were examined by scanning electron microscopy (SEM), electrochemical impedance and voltammetry. The various bismuth plating solutions containing Cl-, Br- and I- respectively, were tested in bismuth-film generation. It has been found that the plating solution only containing Br- ensures the finest quality bismuth film for analytical purposes. Other operational parameters such as extraction time, pH of the electrolytic and sample solution, and co-solvents have been optimized. Under the optimum experimental conditions, the stripping voltammetric response was proportional to the concentration of sudan ranging from 0.1 to 10 M. The detection limit was 0.05 M.