Small extracellular vesicles-enhanced enzymatic activity for sensitive detection

Constructing high-activity natural enzyme and nanozyme catalytic systems have long been a central research goal in biosensing. Small extracellular vesicles (sEVs) are natural nanovesicles with good biocompatibility and unique membrane structure, providing a novel strategy for enzyme activity regulation. Herein, we employ sEVs with cytochrome c (Cytc) and quantum dots (QDs) to construct enhancement Cytc@sEVs and QDs@sEVs enzyme system. The Cytc@sEVs, CQDs@sEVs and WQDs@sEVs exhibit around 15-fold, 2-fold and 12-fold higher peroxidase activity than free Cytc, CQDs and WO₂ QDs, respectively. Benefiting from the enhanced activity of Cytc, the Cytc@sEVs show a low detection limit of 43 particles/μL towards sEVs. The as-constructed sEVs-driven enhancement offers a new route for building high-performance enzyme system.