A label-free ratiometric fluorescence strategy for 3′–5′ exonuclease detection. (17th September 2018)

• Record Type: Journal Article
• Authors: Hu, Wei; Zhao, Hengzhi; Jing, Jing; Zhang, Xiaoling
• Is Part Of: New journal of chemistry. Volume 42:Number 20(2018)
• Page Start: 16630
• Page End: 16634
• Publication Date: 2018-09-17
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c8nj03242d
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : A label-free ratiometric fluorescent biosensor for detection of exonuclease was proposed through utilizing two individual DNA conformation-specific dyes (DAPI and NMM). Abstract : A label-free ratiometric fluorescent platform has been developed for the detection of 3′–5′ exonuclease utilizing two individual DNA conformation-specific dyes. Initially, the DNA substrate maintains a stable HP (hairpin probe) structure, resulting in bright fluorescence at 455 nm for 4′, 6-diamidino-2-phenylindole (DAPI), which is able to insert into A–T base pairs of the HP structure. Upon the addition of 3′–5′ exonuclease (exonuclease III), the HP structure was digested to single-stranded DNA (ssDNA), and the fluorescence intensity at 455 nm was decreased. However the emission of N -methyl mesoporphyrin IX (NMM) at 610 nm was increased significantly due to the formation of G-quadruplex. This label-free method is realized by facile design and shows good selectivity for Exo III detection. More importantly, it also shows its potential as a platform for Exo III inhibitor screening.