DNAzyme cascade circuits in highly integrated DNA nanomachines for sensitive microRNAs imaging in living cells

• Published in: Biosensors & bioelectronics Vol. 177; p. 112976
• Main Authors: Duan, Lu-Ying, Liu, Jin-Wen, Yu, Ru-Qin, Jiang, Jian-Hui
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.04.2021
• Subjects: Biosensing Techniques; DNA Probes; DNA, Catalytic; DNAzyme cascade circuits; Integrated DNA nanomachines; Living cells imaging; MicroRNAs; MicroRNAs - genetics; Split-DNAzyme; Living cells imaging; Integrated DNA nanomachines; MicroRNAs; DNAzyme cascade circuits; Split-DNAzyme
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2021.112976

DNA molecular probes have emerged as powerful tools for fluorescence imaging of microRNAs (miRNAs) in living cells and thus elucidating functions and dynamics of miRNAs. In particular, the highly integrated DNA probes that can be able to address the robustness, sensitivity and consistency issues in a single assay system were highly desired but remained largely unsolved challenge. Herein, we reported for the first time that the development of the novel DNA nanomachines that split-DNAzyme motif was highly integrated in a single DNA triangular prism (DTP) reactor and can undergo target-activated DNAzyme catalytic cascade circuits, allowing amplified sensing and imaging of tumor-related microRNA-21 (miR-21) in living cells. The DNA nanomachines have shown dynamic responses for target miR-21 with excellent sensitivity and selectivity and demonstrated the potential for living cell imaging of miR-21. With the advantages of facile modular design and assembly, high biostability, low cytotoxicity and excellent cellular internalization, the highly integrated DNA nanomachines enabled accurate and effective monitoring of miR-21 expression levels in living cells. Therefore, our developed strategy may afford a reliable and robust nanoplatform for tumor diagnosis and for related biological research. •The novel DNA triangular prism-based DNAzyme cascade circuits were developed for effective miR-21 sensing and imaging.•Target circularly activated inert DNAzyme motif and executed catalytic cleavage circuits for amplified fluorescence signal.•The nuclease resistance of DNA triangular prism was favorable for target sensing and imaging of developed DNA nanomachines.•Highly integrated DNA nanomachines were facile prepared and owned self-delivery ability into cells without extra carrier.