Abstract
Herein, an enzyme-free and label-free fluorescence microRNA biosensor based on cascade amplification of DNAzyme-powered three-dimensional DNA walker and hybridization chain reaction was developed. Firstly, the microRNA hybridized with the locking DNA and caused the locking DNA released from the blocked walking probes (BWPs) through toehold-mediated strand displacement reaction. The DNAzyme was exposed and then the walking probes automatically moved along the three-dimensional tracks and catalyzed the cleavage of hairpin DNA substrates (HDSs), releasing abundant triggers. Finally, the triggers initiated the hybridization chain reaction to generate amplified fluorescence signals. Compared with the three-dimensional DNA walker powered by protein enzyme, this DNAzyme-powered three-dimensional DNA walker was simpler and more stable. The high amplification efficiency of cascade amplification guaranteed a satisfactory sensitivity with a detection limit of 7.9 fM. The toehold-mediated strand displacement reaction guaranteed an admirable specificity. The microRNA analysis in real biological sample further indicated that this biosensor offered an alternative strategy for the quantification of microRNA.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
