In this work, nifedipine (NP) and its main metabolite dehydronifedipine (DHNP) were electrochemically investigated using cyclic voltammetry at the unmodified and modified glassy carbon electrodes. The data show that electrochemical reduction of NO2 group of NP and DHNP results to the generation of Ar–NHOH which can be reversibly oxidized to Ar–NO. This fact is used for the simultaneous determination of NP and DHNP by differential pulse voltammetry (DPV) technique. The results also show that multi-walled carbon nanotube (MWCNT) modified glassy carbon electrode provides better sensitivity and detection limit than unmodified glassy carbon electrode. Performance and structure of modified electrode were characterized by scanning electron microscopy (SEM) and differential pulse voltammetry (DPV). At the optimum conditions, the proposed sensor exhibited a good linear range from 0.1-100 μM with the limit of detection (LOD) values of 0.015 ± 0.2% and 0.017 ± 0.2% μM for DHNP and NP, respectively. The prepared sensor was successfully employed for the simultaneous determination of NP and DHNP in real samples.
