Abstract
•A novel nanoparticle paste electrode was used for electrooxidation of captopril.•A simple method for synthesis on NiO nanoparticles.•This sensor was used for the determination of captopril in patient human urine.
Synthesis and application of NiO nanoparticles (NiO/NPs) and (9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-4-ethylbenzene-1,2-diol (DED) as high sensitive sensors for voltammetric determination of captopril (CAP) using carbon paste electrode has been reported in this work. The synthesized nanoparticles were characterized by different methods such as TEM and XRD. The electrochemical oxidation of CAP on the new NiO/NPs (9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-4-ethylbenzene-1,2-diol carbon paste electrode (NiO/NPs/DED/CPE) has been carefully studied. Under the best experimental conditions selected, the calibration curve for CAP was linear in the concentration range from 0.035 to 550μmolL−1 and a detection limit of 0.007μmolL−1 was obtained. The influence of pH and potential interfering substances on the determination of CAP were studied. Electrochemical impedance spectroscopy (EIS) was used to study the charge transfer properties at the electrode–solution interface. Finally, the sensor was examined as a selective, simple, and precise new electrochemical sensor for the determination of CAP in real samples, such as drugs and urine.