Electrochemical Determination of 3,5-dinitrobenzoic Acid in the Presence and Absence of CTAB at Multi-walled Carbon Nanotubes Modified Glassy Carbon Electrode: A Voltammetric Study

In this work, the glassy carbon electrode (GCE) was modified with multi-walled carbon nanotubes (MWCNTs) by drop casting process, and it was used as a working electrode for the electrochemical determination of 3,5-dinitrobenzoic acid (3,5-DNBA) in an electrolytic solution containing a cetyl trimethyl ammonium bromide (CTAB). This process was examined by using differential pulse voltammetry (DPV) and cyclic voltammetry (CV) techniques. The modified electrode showed an excellent electrocatalytic activity and sensitivity towards the investigation of 3,5-DNBA reduction behavior in the presence of CTAB. The electrochemical process was irreversible and was controlled by adsorption. The effect of pH, scan rate and concentration were studied at the surface of MWCNTs/GCE. The electrochemical behavior of 3,5-DNBA was studied in the presence and absence of CTAB at MWCNTs/GCE in PBS having pH 6.5. The LOD (limit of detection) and LOQ (limit of quantification) of 3,5-DNBA was found to be as 4.94×10-6 M, 1.65×10-5 M respectively. The surface coverage area concentration (Γ) of MWCNTs/GCE was calculated and was found to be as 1.3146×10-8 mole/cm2. By using electrochemical impedance spectroscopy (EIS), the interfacial electron transfer behavior of 3,5-DNBA was studied at different types of electrode surfaces.