Highly sensitive determination of perphenazine on a carbon nanocomposite ionic liquid electrode†
Abstract
Carbon nanomaterial–ionic liquid nanocomposites have provided an impressive class of materials expressly for electrochemical applications. In this work the electrocatalytic oxidation of perphenazine (PPZ) was studied at a carbon nanocomposite electrode, fabricated using multi-walled carbon nanotubes (MWCNT) and the ionic liquid 1-octylpyridinium hexaflourophosphate (OPFP). The surface of the proposed electrode was characterized by scanning electron microscopy. Adsorptive stripping voltammetry (AdSV) was applied as a highly sensitive method for the quantification of sub-micromolar amounts of PPZ. Various parameters were optimized for practical applications. It was found that the electrode showed a sensitive voltammetric response to PPZ. Cyclic voltammetry (CV) was also applied to obtain information about the reaction mechanism and for calculating the kinetic parameters. The oxidation was irreversible and exhibited adsorption controlled behavior. The electron transfer coefficient (α) value was found to be 0.57 from the slope of a Tafel plot. The anodic peak current was linear to PPZ concentration in the ranges of 5.0 × 10−8 to 3.0 × 10−5 M and 3 × 10−5 to 1.5 × 10−4 M, with correlation coefficients of 0.9987 and 0.9917, respectively. The detection limit was 2.3 × 10−8 M. Also for the amperometric procedure a linear dynamic range of 1.0 × 10−5 to 1.2 × 10−4 M with a detection limit of 2.1 × 10−6 M was obtained. The method was successfully applied for determination of PPZ content in pharmaceuticals and blood serum samples.