Green synthesis of copper(II) oxide nanoparticles covered on multiwalled carbon nanotubes modified screen-printed electrode as rapid electrochemical sensing platform for detection of doxepin

Abstract

In the current research, a modified screen-printed electrode has been made by depositing a copper(II) oxide nanoparticle upon the surface of multiwalled carbon nanotubes (CuO/MWCNTs). Through the use of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and mapping, the characterization of the CuO/MWCNTs modifier was examined. The XRD analysis confirms the in-situ formation of copper(II) oxide nanoparticles with MWCNT. FESEM studies reveal the simultaneous existence of nanoparticles and nanotubes in the prepared nanocomposite material. This kind of morphological orientation has significantly improved the nanocomposite’s catalytic properties. Moreover, EDS analysis and elemental mapping depicts that the presence of nanocomposite containing the elements of Cu, O, and C mentioned. Examining the modified electrode's electrochemical activity revealed good stability and conductivity under a diffusion-controlled procedure, making it an ideal working electrode. Additionally, the doxepin oxidation process at the modified electrode’s surface, an antidepressant medicine, has been examined. The modified electrode had a high doxepin sensitivity at an applied voltage of 780 mV. With a detection limit of 0.17 nM (signal/noise = 3), linear range was also obtained over a wide concentration range of 0.001 µM to 400.0 µM (R2 = 0.9998). What's more, the modified electrode is very resistant to ion poisoning and efficiently prevents interference from the oxidation of typicalinterfering species. Moreover, the CuO/MWCNTs electrode has been utilized to measure the doxepin concentration in actual samples. Aside from having an improved electrocatalytic capability, the modified electrode also has a low working potential and good stability, as well as high sensitivity.