Pencil graphite electrode as an electrochemical sensor for the voltammetric determination of chlorpromazine

A selective, simple and sensitive electrochemical sensor has been developed using pencil leads (pencil graphite electrode, PGE) for the investigation of chlorpromazine (CPZ). The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques were employed to study the anodic behaviour of CPZ. The bare PGE showed good electrocatalytic activity towards the determination of CPZ in comparison with alanine and glycine modified PGEs. The PGE showed a well enhanced peak current compared to alanine and glycine modified PGEs for the determination of CPZ. The electroactive surface area, influence of pH, effect of scan rate, electron transfer kinetics and sensitivity have been studied. DPV has shown good linearity in the concentration range of 0.01 μM – 0.08 μM with the limit of detection of 0.003 μM. The proposed sensor has been successfully employed for the determination of CPZ present in a pharmaceutical sample. •A sustainable Pencil Graphite Electrode (PGE) has been developed for the electrochemical determination of Chlorpromazine (CPZ).•Pencil Graphite Electrode showed high electrocatalytic activity, high sensitivity and selectivity, good stability and reproducibility compared to alanine and glycine modified PGE.•The detection limit was found to be 3.002 nM which is much better compared to reported data.•The proposed sensor was successfully employed for the analysis of CPZ in pharmaceutical formulation with good percentage recovery.