Electrochemical Determination of Propranolol using Reduced Graphene Oxide Modified Carbon Paste Electrode

In present work, a cardiovascular drug, propranolol (PROP) has been investigated using reduced graphene oxide modified carbon paste electrode (rGO-CPE). A simple, selective and sensitive method has been developed using cyclic voltammetry (CV), differential pulse voltammetry (DPV), square wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS). At pH-7.0 in 0.1 M phosphate buffer solution (PBS) PROP shows excellent electrooxidation process on rGO-CPE. The EIS data provides charge transfer resistance behaviour at carbon paste electrode (CPE, 96.6 kΩ) and rGO-CPE (46.7 kΩ), which shows the increased electron transfer process at rGO-CPE. The linear calibration curves were obtained in the concentration range of 0.1–2.5 μM (for DPV) and 0.1–5.0 μM (for SWV), respectively. The lower limits of detection values were found to be 0.4×10-8 M and 0.2×10-9 M, respectively. The effect of pH, scan rate, electrode kinetics, electroactive surface area, sensitivity and selectivity on the determination of PROP has been studied. The modified electrode rGO-CPE has been successfully employed for the determination of PROP present in pharmaceutical sample.