Facile fabrication of palm trunk–like ZnO hierarchical nanostructure–based biosensor for wide-range glucose detection

Accurate blood glucose monitoring utilizing nanomaterial-based biosensors has the potential to revolutionize diabetes management. Although offering advantages such as high sensitivity and specificity, nanomaterial-based biosensors also face major issues with stability and reproducibility. Herein, high fabrication reproducibility and sensing performance are demonstrated for a palm trunk–like ZnO hierarchical nanostructure–based glucose biosensor. A hydrothermal synthesis method was successfully utilized to grow palm trunk–like ZnO hierarchical nanostructures on pre-seeded silver (Ag) electrodes, which enabled control of two crucial factors responsible for the excellent sensing performance of the fabricated electrochemical glucose biosensor (i.e., fabrication reproducibility and high enzyme immobilization). The glucose-sensing performance of the developed highly stable and reproducible electrochemical glucose biosensor was demonstrated by its ability to detect glucose concentrations over a wide range (up to 31.6 mM glucose) with high sensitivity (108.15 μA/mM/cm2). Furthermore, the fabricated electrochemical glucose biosensor was applied to human serum samples, with encouraging results. The developed sensor fabrication platform demonstrates the potential for further use in designing different sensors, either by nanomaterial modification or through the use of flexible conductive electrodes.