Development of low-cost, fast, and sensitive voltammetric methods for the determination of donepezil using unmodified carbon paste electrode

Novel voltammetric methods were developed for the determination of donepezil, an acetylcholinesterase inhibitor, using the prepared carbon paste electrode. As a result of the optimization, the carbon paste composition was determined as 25% mineral oil and 75% graphite powder. Quantitative analysis of donepezil was carried out by differential pulse voltammetry (DPV) or square wave voltammetry (SWV) in Britton-Robinson buffer at pH 8.0. Linear ranges were obtained as 0.1‒20 µM with a detection limit of 26.3 nM for DPV and 0.08‒10 µM with a detection limit of 20.4 nM for SWV. The accuracy of the developed methods was obtained as 101.08% and 100.73% for DPV and SWV, respectively, with recovery from pharmaceutical dosage form, indicating that the determination of donepezil could be successfully accomplished without the interference of excipients.