Electrocatalytic determination of chlorpromazine drug using Alizarin Red S as a mediator on the glassy carbon electrode

The anodic oxidation of chlorpromazine (CPZ) has been studied on a glassy carbon electrode by electrocatalytic effect of Alizarin Red S (ARS) as a homogenous mediator in universal buffer (pH = 2). The linear sweep voltammetry (LSV) studies showed that the catalytic current of this system depends on the concentration of CPZ. The magnitude of the peak current for ARS increased severely in the presence of CPZ, and proportional to CPZ concentration. The catalytic peak current was linearly dependent on CPZ concentration in the ranges of 10–500 μM and the detection limit was 5.16 μM by LSV. The diffusion coefficient of CPZ was estimated using chronoamperometry. The method also was used for estimation of catalytic rate constant at catalytic reaction between ARS and CPZ. The influences of potentially interfering substances on the current response of the system were examined. The importance of technique is because of its ability to electrocatalytic determination of CPZ with ARS as homogenous electrocatalyst, while it does not need to be prepared as for the modified electrode. The method was successfully applied for analysis of CPZ in solid pharmaceutical formulations.