Differential Pulse Anodic Stripping Voltammetry Determination of Lead(II) and Cadmium(II) with Multiwalled Carbon Nanotubes- Thiol Functionalized Chitosan Modified Bismuth Film Electrode

Trace elements, especially heavy metals, even at low concentrations (< 2 ppb) are considered to be one of the main sources of pollution in the environment, since they have a significant effect on ecological quality. Among the metal contaminants, heavy metal ions such as Pb and Cd are the two major pollutants which can cause profound biochemical and neurological changes in the body. The major sources of lead arise from the burning of leaded gasoline in vehicle and the industrial releases due to lead mining, smelting and refining operations. Other potential sources of lead in the environment include lead-acid batteries, paints, incinerators and waste disposal. On the other hand, the major sources of cadmium are from industrial emission from smelter and metallurgical processing, incineration, nickel-cadmium batteries, cadmium pigmented plastics, ceramics, glasses, paints and enamels. The determination of heavy metal ions has been of prime importance. Different techniques and methods, including atomic absorption spectroscopy, inductively coupled plasmaatomic emission spectroscopy, inductively coupled plasmamass spectrometry, ion chromatography and a variety of electrochemical techniques have been used for the analysis of heavy metals in water resources and food materials. Electrochemical stripping voltammetry has long been recognized as a powerful technique for trace metals owing to Differential Pulse Anodic Stripping Voltammetry Determination of