Determination of Some Phenothiazines Compounds in Pharmaceuticals and Human Body Fluid by Electrocatalytic Oxidation at a Glassy Carbon Electrode Using Methylene Blue as a Mediator

Abstract

A glassy carbon electrode plus Methylene blue as a mediator was employed to study and sense the electrocatalytic oxidation of phenothiazines, including chlorpromazine, perphenazine, promazine, and fluphenazine, using cyclic voltammetry and chronoamperometry as diagnostic techniques. The electron-transfer coefficient, alpha (= 0.45), for phenothiazines compounds at the surface of glassy carbon electrode was determined using a cyclic voltammetry technique. It was found that under a selected pH (8.6) the peak current due to the oxidation of Methylene blue at the surface of the electrode that occurrs at a potential of about − 180 mV is proportional to the phenothiazines concentration. Linear analytical curves were obtained in the ranges of 1.0 × 10⁻⁶ − 2.1 × 10⁻⁴ mol L⁻¹ for the phenothiazines compounds. The influences of potentially interfering substances on the current response of the system were examined. The method was used for the determination of phenothiazines compounds, including chlorpromazine, perphenazine, promazine, and fluphenazine in human.

Keywords:

• Electrocatalyst
• methylene blue
• phenothiazines
• voltammetry

The authors thank the Center of Excellency in Sensors (IUT) and the IUT Research Council for supporting this work.

Notes

*Maximum concentration of the substances tested.