Voltammetric analysis of epinephrine using glassy carbon electrode modified with nanocomposite prepared from Co-Nd bimetallic nanoparticles, alumina nanoparticles and functionalized multiwalled carbon nanotubes.

Herein, we investigated the electrochemical behaviour of fMWCNTs decorated with Co-Nd bimetallic nanoparticles and alumina nanoparticles (Co-Nd/AlO@fMWCNTs). The nanocomposites were synthesised using simple mechanical mixing and characterised by FT-IR, XRD, UV-visible studies, SEM, TEM and EDAX. Moreover, the crystalline size of the synthesised nanoparticles was also calculated using XRD data (Debye-Scherer formula) and was found in the nm range. The electrochemical behaviour of epinephrine (EP) was examined in the presence of Co-Nd/AlO@fMWCNTs nanocomposite modified glassy carbon electrode (GCE) using various electrochemical techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and chronocoulometry. Among all the above-mentioned techniques, the DPV response of the modified Co-Nd/AlO@fMWCNTs/GCE under optimal circumstances revealed a dual linear range (0.2 to 4000 µM and 4000 to 14,000 µM) and LOD of 0.015 µM (S/N = 3). The sensitivities were determined to be 0.00323 µAµM and 0.0004 µAµM in 0.2 to 4000 µM and 4000 to 14,000 µM concentration ranges. Using chronocoulometry, the surface coverage of Co-Nd/AlO@fMWCNTs/GCE was calculated to be 1.37 × 10 mol cm. The fabricated Co-Nd/AlO@fMWCNTs/GCE demonstrated remarkable repeatability, with an RSD of 0.09%, and storage stability of 3 weeks, with 89.6% current retention. Lastly, it was found that Co-Nd/AlO@fMWCNTs/GCE worked well for EP analysis in a variety of biological fluids.