Dual-Aptamer-Assisted AND Logic Gate for Cyclic Enzymatic Signal Amplification Electrochemical Detection of Tumor-Derived Small Extracellular Vesicles

Abstract

Small extracellular vesicles (sEVs), often referred to as exosomes, are potential biomarkers for noninvasive cancer diagnosis. However, because of their phenotype heterogeneity, precise detection of tumor-derived sEVs is a great challenge. Herein, a dual-aptamer-assisted AND logic gate was fabricated for sensitive electrochemical detection of tumor-derived sEVs based on a cyclic enzymatic signal amplification strategy. Four different tumor-derived sEVs were used to verify the feasibility of the AND logic gate, and CCRF-CEM sEVs were successfully detected by this assay. The electrochemical assay shows a good linear response from 4 × 10³ to 8 × 10⁷ particles/μL, with a detection limit of 920 particles/μL, for CCRF-CEM sEVs, indicating potential application in accurate cancer diagnostics.