Inspection of electrochemical behavior of tolnaftate a topical antifungal agent and its active hydrolysis products by disposable screen-printed carbon electrode

Abstract

Inspection of the electrochemical behavior tolnaftate (TNF), of a topical antifungal agent and its active hydrolysis products, was carried out by utilizing a disposable screen-printed carbon electrode (SPCE) for the first time. The voltammetric behavior of TNF was studied in various pH values using cyclic voltammetry and differential pulse voltammetry. A well-defined irreversible oxidation wave of TNF was observed at 1.20 V (vs. pseudo Ag/AgCl) and did not shift with different pH of solutions. The electro-analytical performance of the disposable SPCE was investigated in wide concentration ranges with limits of detection (LOD) of 0.24 μM and 3.76 μM in 0.1 M H2SO4 and B.R. buffer pH 7, respectively. Thus, the disposable SPCEs offer a sensitive and reproducible electrochemical platform for TNF in dosage forms. Further, the TNF was hydrolyzed in an alkaline medium to release its possible lethal products i.e. 2- Naphthol which can be analyzed voltammetrically without any interference so it is considered as a first selective stability-indicating assay for TNF.