Nickel Cobalt Oxide Nanoparticles-decorated Multi-walled Carbon Nanotubes as a High-performance Sensing Platform for the Detection of Tramadol in Human Biofluids

Abstract

This study reports the synthesis of the nickel-cobalt oxide nanoparticles-decorated multi-walled carbon nanotubes (MWCNTs@NiCo₂O₄ NPs) as a high-performance nanocomposite with electrochemical advantages for the first time. The synthesis principle of this novel eco-friendly nanocomposite relies on the deposition of the NiCo₂O₄ NPs on the MWCNTs' walls by a simple hydrothermal method under the green chemistry indexes. The surface coverage (Γ) of the redox species of NiCo₂O₄ NPs in the proposed nanocomposite has been calculated to be 5.66 µmol cm^-2. This porous nanocomposite has been well utilized for fabricating an electrochemical sensor for detecting tramadol (TRA) because making a specific interaction between its redox species and TRA. The developed sensor can quickly measure TRA in human serum and urine samples under a micromolar (µM) to millimolar (mM) concentration range. Since monitoring this TRA level has been alarmed by the International Association of Forensic Toxicologists (TIAFT) report this sensor may be applicable for legal and clinical organizations. The well-evaluated greenness of the applied methodology according to the international common metric systems along with other bonuses for on-site, quick, and non-invasive measurement of TRA are the advantages of the proposed nanocomposite that may widen for other electrochemical applications.