Electrochemical Detection of Tumor Cell-Derived Exosomes Based on Cyclic Enzyme Scission and Hybridization Chain Reaction Dual-Signal Amplification

Tumor cell-derived exosomes are considered a potential source of cancer biomarkers. Here, we developed an electrochemical sensing platform for the rapid and simple detection exosomes, using CCRF-CEM exosome as model. The utilizes cyclic nicking enzyme cleavage hybridization chain reaction (HCR) dual-signal amplification. A hairpin aptamer probe (HAP) containing was designed assay. specific binding between PTK7, present on surface, causes conformational change in HAP. This facilitates HAP linker DNA, which subsequently triggers endonuclease towards DNA. Therefore, is transformed into DNA detection. By combining this approach with HCR signal amplification, achieved high-sensitivity down to 1.1 × 104 particles/mL. Importantly, assay effectively detected tumor complex biological fluids, demonstrating clinical diagnosis.