Efficient Nonenzymatic Electrochemical Detection of Glucose Using CuO Nanoparticles@CNT-Wrapped Graphene Oxide Composite Electrode

Abstract

A highly sensitive and stable nonenzymatic glucose biosensor has been developed via composite materials composed of CuO and graphene oxide (GO)/carbon nanotube (CNT) nanohybrid (CuO/GO/CNTs). Copper oxide nanoparticle(NP)-modified CNTs were stacked via graphene sheets and synthesized through hydrothermal method, providing a larger surface area with boosted catalytic activity for efficient mass and electron passage, respectively. Scanning electron microscopy (SEM) and energy-dispersive x-ray (EDX) spectroscopy have been used to investigate the morphology and composition of as-prepared nanohybrids, whereas x-ray diffraction (XRD) patterns provide information about the crystal structure and lattice parameters. Fabricated nanohybrid was used as electrode material to develop the nonenzymatic glucose biosensor, which exhibited better performance with a linear dynamic range from 0.06 to 0.74 mM, a high sensitivity of 328 mA mM⁻¹ cm⁻² and a low detection limit of up to 0.033 mM with a fast response time of 2 s. Although the stability and reusability of the fabricated electrode have been tested. The limit of detection was determined by using the traditional formula LOD = (SNR × σ)/Slope. The outcomes recommend the synthesized novel structured nanohybrid as a promising material possessing significant impact for flexible and wearable biosensing applications.