Exonuclease III-assisted positive feedback signal amplification strategy for ultrasensitive electrochemical detection of nucleic acids

摘要: Abstract Diffusion-mediated homogeneous electrochemical assay has attracted substantial attention owing to its simplicity, rapid response, and high recognition efficiency, however, lack of inherent connection between signal reporter electrode surface restricts the improvement detection sensitivity further limits potential applications. Herein, a facile strategy is proposed through integrating advantages traditional heterogeneous homogenous assay. In this strategy, small amount target DNA can trigger release assist from surface. Then, induce amplification reaction, which in turn promotes on by generating numerous analogues, thereby realizing positive feedback amplification. As result, ultrasensitive nucleic acids was achieved dynamic range 5 aM 5 fM with limit down 1.2 aM. There about 2.5 orders magnitude compared control without Moreover, demonstrated selectivity, reproducibility, capability detecting serum samples, displaying promising development biosensing platform for disease diagnosis