Journal of Electroanalytical Chemistry, Vol.788, 7-13, 2017
Electrochemical analysis of amlodipine in some pharmaceutical formulations and biological fluid using disposable pencil graphite electrode
A reproducible and sensitive voltammetric procedure has been developed for the determination of amlodipine (AML) by using pencil graphite electrode (PGE) as working electrode. The experimental parameters, such as concentration, pH, amplitude, frequency, deposition potential were optimized and the peak potential was found to be 700 mV [vs. Ag/AgC1], by square-wave voltammetry (SWV) and differential pulse voltammetry (DPV). Under optimized conditions in Britton-Robinson buffer (pH 8.5), linear calibration curve was obtained in the range of 0.8 nM-51 2 nM solution. The limit of detection (LOD) and limit of quantification (LOQ) for SWV and DPV were calculated 0.02 pM, 0.04 pM, 0.06 pM and 0.2 pM respectively. The proposed method was used to estimate the amount of drug in different brands of pharmaceutical formulations with almost 99.9% recovery. Developed method was also applied for the detection of AML in spiked human serum with good recovery of almost 99% and limit of detection was found to be 021 pM. The proposed methodology is first attempt to develop a method on PGE which represents an effective, cheap, easily available and alternative tool instead of commonly used glassy carbon and other chemically modified electrodes for the electrochemical determination of amlodipine. (C) 2017 Elsevier B.V. All rights reserved.
Keywords:Amlodipine;Square-wave voltammetry;Differential pulse voltammetry;Cyclic voltammetry;Pencil graphite electrode