Abstract

Background: Benserazide is an important catechol drug that has been comprehensively used as an irreversible inhibitor of peripheral aromatic amino acid decarboxylase. It is an important drug with wide application in treatment of Parkinson's disease. Therefore, the determination of this drug is very important in biological samples.

Methods: According to importance of BZ in biological and pharmaceutical samples, we focused on determination of this drug in real samples. In between and analytical methods, electrochemical based sensors have good choice for the determination of drug samples.

Results: The aim of the present study was using CdO/SWCNTs nanocomposite and Ionic liquid (n-hexyl-3- methylimidazolium bromide) for modification of carbon paste electrode. The proposed sensor was applied to the determination of benserazide (BZ). Under optimum pH of 7.0, the electro-oxidation of BZ at a surface of modified electrode occurred at a potential of about 250 mV and oxidation current was more than bare carbon paste electrode. The plot of oxidation signal vs. concentration of BZ was linear in the range of 0.1 to 450.0 μM BZ and detection limit was calculated to be 0.06 μM BZ. The new sensor was also examined for the determination of BZ in real samples.

Conclusion: In this study, we describe synthesis of CdO/SWCNTs by direct chemical precipitation method and synthesized nanocomposite characterized with XRD and TEM methods. In continuation, a carbon paste electrode modified with CdO/SWCNTs and 1-methyl-3-butylimidazolium bromide has been utilized for voltammetric analysis of BZ in pharmaceutical and water samples. In the best electrochemical condition, the oxidation peak current was proportional to the BZ concentration in the range of 0.1–450.0 μM with the detection limit of 0.06 μM.

Keywords: Benserazide analysis, CdO/SWCNTs nanocomposite, sensor, modified electrode, carbon paste electrode, voltammetric sensor.

Graphical Abstract