Differential Pulse Anodic Stripping Voltammetric Determination of Lead (II) Using Poly Xylenol Orange Modified Electrode

In this work a method for sensitive anodic stripping voltammetric determination of Pb(II) ions using a poly xylenol orange film modified electrode (PXOFME) has been proposed. Poly xylenol orange film (PXOF) was formed on a paraffin impegrenated graphite electrode (PIGE) using electro polymerization method by scanning the potential between -0.5V to 1.3V, at a scan rate of 50mV/s for 30 segments in 0.1M phosphate buffer solution (PBS) of pH7. The PXOFME was characterized by scanning electron microscopy (SEM), ATR-IR spectroscopy, cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The modified electrode has been used to develop a sensitive method for the determination of Pb(II) ions by anodic stripping voltmmetry (ASV). The PXOFME was used to preconcentrate Pb(II) ions through complexation, the complexed metal ions were reduced electrochemically and then stripped anodically from the surface of the electrode. A linear range of 5g/L to 413g/L with a limit of detection (S/N=3) of 1.6g/L was observed for the determination of Pb(II) ions. The method was applied to lead determination in sea water and tap water samples and the results were found to be satisfactory.