Facile microwave-assisted growth of 3D ZnVO nanomarbles on graphene oxide nanosheets for simultaneous detection of ascorbic acid, dopamine, and uric acid

Simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA) is challenging due to close oxidation potential. These biomolecules lie in the human body and have significant roles in many psychological reactions. A slight change in the concentration of these molecules can cause serious health issues; in this context, accurate and timely detection holds significant value in clinical diagnostics. This work demonstrates the synthesis of 3D zinc nanomarbles on 2D graphene oxide sheets using a rapid and environmentally friendly microwave-assisted technique. The porous morphology with thin nanomarbles where (2 2 0) reactive sites were exposed to the environment with enhanced surface area measured 38.29 m² g⁻¹. The composite ZnVO/rGO has been employed on glassy carbon electrodes, resulting in superior electrocatalytic properties that enable the simultaneous detection of these analytes with wide potential gaps. Notably, the ZnVO/rGO/GCE exhibits simultaneous detection with a working range of AA (100 µM-1000 µM), DA (10 µM-100 µM), and UA (10 µM-100 µM). The detection limits were estimated to be 4.3 µM, 0.7 µM, and 0.32 µM, respectively. The ZnVO/rGO/GCE sensor demonstrates remarkable stability, selectivity, reproducibility, and satisfactory recovery during real sample analysis. The high surface area, porous nature, and thin size of 3D nanomarbles enhance charge transportation, making it promising for electrochemical performance. This study lays the foundation for future advancements in human health monitoring by introducing a novel approach.