Target Extension‐Activated DNA Walker on Nanoparticles for Digital Counting‐Based Analysis of MicroRNA†. Issue 6 (4th May 2021)

• Record Type: Journal Article
• Authors: Feng, Qinya; Zhai, Yuqing; Ren, Wei; Liu, Chenghui
• Is Part Of: Chinese journal of chemistry. Volume 39:Issue 6(2021)
• Page Start: 1471
• Page End: 1476
• Publication Date: 2021-05-04
• Subjects: RNA recognition -- DNA cleavage -- Digital counting -- Total internal reflection fluorescent microscope -- Nanoparticles; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cjoc.202000692
• Languages: English
• ISSNs: 1001-604X

Abstract

Main observation and conclusion: MicroRNAs (miRNAs), especially exosomal miRNAs, are promising noninvasive biomarkers in early‐stage cancer diagnosis and disease treatment monitoring. However, their precise and sensitive quantification remains challenging due to their small size and low abundance. Herein, we have developed a nanoparticle‐confined DNA walker strategy for the specific detection of miRNA. In the existence of the target miRNA, the on‐particle DNA walking reaction will be initiated, providing a fluorescence‐positive nanoparticle. Otherwise, the nanoparticle would be fluorescence‐negative. Utilizing the total internal reflection fluorescent microscope (TIRFM) to digitally count the fluorescence‐positive nanoparticles, the proposed method possesses a detection limit of 0.2 pmol/L miRNA and can accurately distinguish the single‐base mismatched target. This design combines the merits of the DNA walker for signal amplification and the TIRFM for highly sensitive detection, paving a new way for the digital counting‐based analysis of exosomal miRNAs. Abstract : A new DNA walking mechanism is developed for the digital counting‐based analysis of miRNA.