Electrochemical study of niclosamide at poly(3,4-ethylenedioxythiophene) modified glassy carbon electrode

A poly(3,4-ethylenedioxythiophene) (PEDOT) modified glassy carbon electrode was constructed for the determination of niclosamide. Cyclic voltammetry and differential pulse anodic stripping voltammetry were used to study the electrochemical reaction of niclosamide at the modified electrode in pH 7.0 phosphate buffer solution. The PEDOT-modified electrode showed a very good electrochemical behavior with a significant enhancement of the peak current compared to the bare electrode. The pH of the solution, accumulation potential and preconcentration time were optimized and the analytical performance of the modified electrode was investigated. A linear voltammetric response for niclosamide was obtained in the concentration range of 0.075–7.50 μM, with a detection limit of 1.09 × 10−8 M. The method was successfully applied for the determination of niclosamide in pharmaceutical formulation and biological sample.