Application of two-dimensional zeolitic imidazolate framework-L (Co)/multi-walled carbon nanotube nanocomposite modified electrode as a sensitive voltammetric sensor for determination of cannabidiol

Abstract

In this study, a two-dimensional (2D) leaf-like zeolitic imidazolate framework-L (Co)/multi-walled carbon nanotubes (2D ZIF-L (Co)/MWCNTs) nanocomposite was synthesized using a simple method and utilized as an effective material for voltammetric determination of cannabidiol (CBD). The morphology, structure, and composition of the synthesized ZIF-L (Co)/MWCNTs were characterized through techniques including field-emission scanning electron microscopy (FE-SEM), X-ray powder diffraction (XRD), and Energy Dispersive X-ray spectroscopy (EDS). The screen-printed electrode (SPE) modified with ZIF-L (Co)/MWCNTs was fabricated by the drop-casting of ZIF-L (Co)/MWCNTs suspension on the SPE surface. To study the electrochemical behavior of CBD, cyclic voltammetry (CV), chronoamperometry, and differential pulse voltammetric (DPV) analysis was performed, and compare the oxidation behavior on ZIF-L (Co)/MWCNTs/SPE and bare SPE. The peak current of the DPV of CBD showed a linear increase with its concentration in the range of 0.5 μM – 280.0 μM, and a low detection limit (LOD) of 0.02 μM was achieved. Moreover, the proposed sensor was successfully used to determine CBD in real specimens.