Functional enzyme-metal nanogel for efficient glucose detection using interface supramolecular adhesion and adsorption

Glucose offers basic power for the daily activities of human beings, and the concentration of glucose in serum influences health. At present, the main problems faced by nanogel glucose detection include: the sensitivity and selectivity need to be further improved, and the long-term in vivo stability is insufficient. Here, a cyclodextrin-based multi-functional nanogel was synthesized for glucose detection. In such a nanogel, glucose oxidase (GOx), chitosan (CS) and β-cyclodextrin (β-CD) were cross-linked in the nanogel net and Fe ions coordinate with multiple groups and cyclodextrin lumen. A cascade catalysis of GOx and Fe nanoparticle could enhance the detection sensitivity for better sensitivity. 1 H ‌nuclear magnetic resonance result confirmed that β-CD has a host-guest interaction with the substrate glucose for better catalysis with GOx for selectivity. Moreover, the Fe coordination with nanogel make the structure stable for long-term detection. Overall, the Fe-based nanogel strategy provides a new glucose detection method.