Electrochemiluminescence detection of miRNA-21 based on dual signal amplification strategies: Duplex-specific nuclease -mediated target recycle and nicking endonuclease-driven 3D DNA nanomachine

• DOI: 10.1016/j.bios.2023.115116
• Publication Date: 2023-02-02T09:04:28Z
• Authors: Ming-Yue Wang; Wen-Jie Jing; Li-Juan Wang; Li-Ping Jia; Rong-Na Ma; Wei Zhang; Lei Shang; Xiao-Jian Li; Qing-Wang Xue; Huai-Sheng Wang
• Keywords: Nuclease; Rolling circle replication; Electrochemiluminescence; A-DNA; Duplex (building)

DNA nanomachines have shown potential application in the construction of various biosensors. Here, an electrochemiluminescence biosensor for the sensitive detection of miRNA-21 were reported based on three-dimensional (3D) DNA nanomachine and duplex-specific nuclease (DSN)-mediated target recycle amplification strategy. First, the bipedal DNA walkers were obtained by DSN-mediated digestion reaction initiated by target miRNA-21.3D DNA tracks were prepared by modifying Fe3O4 magnetic beads (MBs) with ferrocene-labeled DNA (Fc-DNA). The produced DNA walkers autonomously moved along 3D DNA tracks powered by nicking endonuclease. During the movement, ferrocene-labeled DNA was cleaved, resulting in large amounts of Fc-labeled DNA fragments away from the MBs surface. Finally, the liberated Fc-labeled DNA fragments were dropped on the C-g-C3N4 modified electrode surface, leading to the quenching of C-g-C3N4 electrochemiluminescence (ECL). Benefiting from the dual amplification strategy of 3D DNA nanomachine and DSN-mediated target recycling, the developed ECL biosensor exhibited an excellent performance for miRNA-21 detection with a wide linear range of 10 fM to 10 nM and a low detection limit of 1.0 fM. This work offers a new thought for the application of DNA walkers in the construction of various biosensors.