Reusable electrochemical non-enzymatic glucose sensors based on Au-inlaid nanocages

Mass detection of glucose, which is required in many applications, remains challenging. The commercial enzyme-based glucose test strips cannot be reused, and current non-enzymatic glucose sensors exhibit a narrow range of detection and slow glucose oxidation kinetics. Herein, controlled etching of Prussian blue analogue (PBA) nanocubes at the vertices is conducted and Au nanoparticles (Au NPs) are subsequently inlaid in the etched cavities by in-situ reduction of HAuCl4. The unique AuNP-PBA nanocomplexes exhibit low electrochemical potential for glucose oxidation, high electrocatalytic activity, and rapid redox electron transfer rate. Covalent immobilization of the Au-inlaid nanomaterials on a fine Au wire leads to a non-enzymatic glucose sensor with a particularly wide linear detection range (10 µM to 16 mM), excellent anti-interference, and fast response. More importantly, the sensor is reusable, and its sensitivity is well maintained even after 150 times of detection. This new-concept material promises to enable high-throughput glucose detection at a low cost, which is essential in diabetic management and other healthcare applications.