A precision miRNA-21 detection method based on self-powered biosensors

Early detection and treatment are effective strategies to reduce cancer mortality. Self-powered biosensors based on enzyme biofuel cells are rapid, high-sensitivity, and low-cost analysis methods with various detection modes, demonstrating great advantages as detection platforms for liquid biopsy. Aiming to further improve the detection sensitivity of self-powered biosensor platforms, this study adopted the Toehold-mediated hybridization chain reaction, which improved the detection sensitivity while accurately identifying common cancer markers. Experimental data showed that the open-circuit voltage of the well-designed biosensor platform had a good linear relationship with the logarithm of miRNA-21 concentration in the range of 0.0001-100 pmol/L with a low limit of detection of 5 amol/L (S/N=3), preliminarily confirming the quantitative analysis capability of the platform. Therefore, the designed biosensor platform can facilitate clinical detection and improve early cancer detection accuracy.