Electrochemical study of methimazole and its direct determination in pharmaceutical preparations and human serum by square wave and differential pulse voltammetry

Abstract

Two simple and rapid methods were developed for the determination of methimazole in pharmaceutical preparations and human serum by square wave and differential pulse voltammetry. The anodic peak at +0.60 V obtained in a buffer on glassy carbon electrode was used for analysis. The peak current and peak potential depend on pH, scan rate and initial potential. Decrease of the anodic peak with increasing pH, as well as deviations from linear plots of ip = f(C) and ip = f(C) and ip = kv1/2 indicate that this peak at higher concentrations is affected by adsorption-desorption phenomena. The linearity was established over the concentration range of 10-80 ug/mL for both methods in supporting electrolyte and human serum. The repeatability and reproducibility of the methods for all media (such as supporting electrolyte and serum samples) were determined. Precision and accuracy were also checked in all media. Developed methods in this study can be applied to Thyromazol tablet. Also, the proposed techniques were successfully applied to spiked human serum samples. No electroactive interferences from the endogenous substances were found in the serum samples.