Search

With the emergence of microRNAs as key biomarkers for disease diagnosis such as lung cancer, various techniques have been settled for their detection. However, these current methods require different amplification steps since numerous challenges for detecting circulating miRNAs are attributable to their intrinsic properties accounting for tiny sizes, high sequence similarity, and low abundance. Duplex specific nuclease (DSN)-based microRNA amplification has recently gained interest in biosensing applications thanks to its catalytic activity based on target recycling. In this context, we designed a highly selective, sensitive, and multiplexed fluorescence-based biosensor combining DSN enzyme and magnetic beads to detect three distinct microRNAs, including microRNA-21, microRNA-210, and microRNA-486-5p. By exploiting the above approach, we were able to detect as low as 98 aM, 120 aM, and 300 aM of mir-21, miR-210, and miR-486-5p, respectively. Furthermore, this recommended strategy displays a high selectivity toward an entirely matched target than the off-target. These results are ascribed to the potent DSN enzyme activity and to the locked nucleic acid (LNA)-modified DNA probe that boosted the hetero-duplex probe/target stability. Lastly, our proposed method was applied to detect microRNAs in the serum samples and displayed a high efficacy to discriminate between healthy controls and lung cancer patients. Furthermore, the analytical accuracy of the proposed strategy was validated with the computed tomography (CT) technique of the chest. Thus based on these findings, this strategy could open new directions for detecting microRNAs associated with several diseases. [Display omitted] • A multiplexed fluorescence-based biosensor combining DSN enzyme and LNA probe tethered MBs for microRNAs detection was settled. • The developed method exhibited a high sensitivity and selectiovity for lung cancer (LC) diagnosis. • The engendered limit of detection is equal to 98 aM, 120 aM, and 300 aM of mir-21, miR-210, and miR-486-5p, respectively. • Via using this serum 3-microRNAs signature, we were able to distinguish LC disease patients from healthy volunteers. • Our proposed method was validated by computed tomography and revealed a high correlation. [ABSTRACT FROM AUTHOR]