High-Performance Graphdiyne Oxide/Au Nanoparticle Electrode for Electrochemical Non-enzymatic Glucose Sensor

Developing a convenient and high-performance blood glucose sensor is crucial for the effective diagnosis and management of diabetes. Sweat sensing offers a noninvasive method for detecting glucose levels; however, the complexities involved in enzyme immobilization and their sensitivity to environmental conditions during detection pose significant challenges in the development of enzyme-based sensors. Herein, this work proposes a graphdiyne oxide/gold nanoparticles (GDYO/AuNPs) composite electrode for nonenzyme glucose detection in sweat. The resulting sensor achieves a remarkable sensitivity (168 μA mM^-1 cm^-2), along with a low detection limit (4.11 μM). Such performance stems from the synergetic effect between AuNPs and the oxygen-rich functional groups of the GDYO substrate. This combination greatly enhances the dehydrogenation process during glucose oxidation. Moreover, the sensor exhibits superior selectivity with the coexistence of four other common substances in human sweat and maintains its glucose detection capabilities under neutral or slightly acidic conditions. Additionally, a GDYO/AuNPs-based wearable glucose sensor successfully monitors glucose fluctuations in human sweat both before and after meals, demonstrating a high correlation with blood glucose levels. Our findings provide a promising electrode for advancing nonenzymatic glucose sensors for in situ monitoring of sweat glucose.