Preparation of a new electrochemical sensor based on iron (III) complexes modified carbon paste electrode for simultaneous determination of mefenamic acid and indomethacin.

A new chemically modified carbon paste electrodes based on Fe (III) schiff base (Fe (III)-SBMCP)-containing graphite pastes were prepared and evaluated as electrochemical sensor for the voltammetric determination of mefenamic acid and indomethacin in aqueous solutions. The measurements were carried out by application of the differential pulse voltammetry (DPV) method in phosphate buffer solution with pH 3.5. Fe (III) loaded in schiff base can increase anodic peak currents by adsorption of mefenamic acid and indomethacin on electrode surface. The prepared electrode shows voltammetric responses with high sensitivity for mefenamic acid and indomethacin in optimal conditions, which makes it very suitable for simultaneous determination of these compounds. The proposed method was successfully applied for determination mefenamic acid and indomethacin in commercial tablet samples.