Title
Thiazole orange modified carbon dots for ratiometric fluorescence detection of G-quadruplex and double-stranded DNA
Author
Ming Jin, Xiangjun Liu, Xin Zhang, Linlin Wang, Tao Bing, Nan Zhang, Yun Zhang, Dihua Shangguan
Year
2018
Journal
ACS Applied Materials & Interfaces
Abstract
A new carbon dots (CDs) based nanoprobe for ratiometric fluorescence detection of DNA was constructed in this work. Thiazole orange (TO), a specific organic small molecular probe towards DNA, is covalently linked to the surface of CDs, acting as the recognition element and fluorescence response unit. In the absence of DNA, the nanoprobe only emitted the blue fluorescence of CDs, while TO was almost non-fluorescent. Upon addition of DNA, a turn-on emission at 530 nm appeared and gradually enhanced along with the increasing of the target DNA, while the fluorescence of CDs kept unchanged, which realized the ratiometric detection of the target DNA. The CDs-TO nanoprobe showed good selectivity to parallel G-quadruplex (G4) and double-stranded (ds) DNA over antiparallel G4 and single-stranded DNA. Moreover, the ratiometric fluorescence nanoprobe exhibited high sensitivity for ssab (a dsDNA) and c-myc (a parallel G4) with a low detection limit of 0.90 and 3.31 nM, respectively. Additionally, the G4/hemin peroxidase activity inhibition experiment demonstrated that CDs-TO bound to the G4s through end-stacking mode.
Full Article
Instrument
J-815
Keywords
Circular dichroism, DNA structure, Chemical stability, Nanostructures, Materials, Biochemistry