Facile Synthesis of Eggshell Membrane-Templated Au/CeO₂ 3D Nanocomposite Networks for Nonenzymatic Electrochemical Dopamine Sensor

Abstract: Dopamine acts as a neurotransmitter to regulate a variety of physiological functions of the central nervous system. Thus, the fabrication of electrochemical active nanomaterials for sensitive dopamine detection is extremely important for human health. Herein, we constructed a highly efficient dopamine nonenzymatic biosensor using eggshell membrane (ESM) as a 3D network-like carrier-loaded Au and CeO₂ nanocomposites. This approach has led to the uniform distribution of CeO₂ and Au nanoparticles on the surface of ESM. The structure and properties of the as-prepared ESM templated Au/CeO₂ (ESM-AC) nanocomposites were characterized. The electrochemical properties of non-enzymatic oxidation of dopamine by ESM-AC electrode were studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The detection limit of the ESM-AC modified electrode for dopamine is 0.26 μM with a linear range from 0.1 to 10 mM. The ESM-AC-modified electrode performs a higher catalytic activity for dopamine electrocatalytic oxidation than that ESM-templated CeO₂ (ESM-C) electrode, which is mainly due to the unique structure of ESM and more active sites provided from Au. Collectively, this biological waste-ESM provides a cheap and unique template for the preparation of 3D network-like nanostructures and expands the application in electrochemical dopamine detection. Graphical abstract: ESM-AC nanocomposites prepared from biological waste was successfully modified on the surface of glassy carbon electrode and a dopamine-based electrochemical biosensor was constructed.[Figure not available: see fulltext.].