Electrochemical evaluation of the desloratadine at bismuth film electrode in the presence of cationic surfactant: Highly sensitive determination in pharmaceuticals and human urine by Linear sweep-cathodic stripping voltammetry

In this study, the electrochemical properties of desloratadine, which is in the second generation antihistamines group, were determined by bismuth film electrode (BiFE) in aqueous and aqueous/surfactant solutions. This compound gave an irreversible and diffusion-controlled reduction peak at about –1.65 V by cyclic voltammetry. It was found that the addition of cationic surfactants (cetyltrimethylammonium bromide (CTAB) increased the reduction current signal of desloratadine, while anionic (sodium dodecylsulfate (SDS) and nonionic (Tween 80) surfactants were found to have an adverse effect. Using linear sweep-cathodic stripping voltammetry, the analytical signal showed a linear correlation with a concentration of 0.1 to 4 µM in 0.04 M Britton–Robinson solution (pH = 8.0) in the presence of 5 mM CTAB, while the detection limit was calculated to be 11.70 nM (3.64 μgL(–1)). This method has been successfully applied for the quantitation of desloratadine in pharmaceutical and urine samples without the need for any separation.