Duplex-Specific DNase Signal Amplification Allows Attomolar Electrochemical Detection of MicroRNAs

Point-of-care biosensors for detecting blood-circulating nucleic acids hold significant potential for disease diagnosis. However, achieving both high sensitivity and accessibility remains a challenge. Electrochemical hybridization assays offer a promising approach for detecting specific nucleic acid sequences but are typically limited to picomolar concentrations. Here, a duplex-specific DNase-assisted electrochemical hybridization assay is presented, enabling highly sensitive nucleic acid detection. By incorporating duplex DNase, the method achieves detection limits as low as 1 attomolar, significantly enhancing sensitivity. This work paves the way for ultrasensitive nucleic acid detection in critical point-of-care applications.