Increasing the Sensitivity and Single-Base Mismatch Selectivity of the Molecular Beacon Using Graphene Oxide as the "Nanoquencher"

• Published in: Chemistry : a European journal Vol. 16; no. 16; pp. 4889 - 4894
• Main Authors: Lu, Chun-Hua, Li, Juan, Liu, Jing-Jing, Yang, Huang-Hao, Chen, Xi, Chen, Guo-Nan
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 26.04.2010; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: Base Sequence; Beacons; Binding, Competitive; biosensors; Chemical compounds; Chemistry; Deoxyribonucleic acid; DNA; DNA - analysis; DNA - chemistry; DNA recognition; Fluorescence; Fluorescent Dyes - chemistry; Graphene; molecular beacons; Nanostructure; Nanotechnology; Nanotubes, Carbon; Oligonucleotide Probes - analysis; Oligonucleotide Probes - chemistry; Oligonucleotides; Oligonucleotides - chemistry; Oxides; single-base mismatch
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.200903071

Here, we report a novel, highly sensitive, selective and economical molecular beacon using graphene oxide as the “nanoquencher”. This novel molecular beacon system contains a hairpin‐structured fluorophore‐labeled oligonucleotide and a graphene oxide sheet. The strong interaction between hairpin‐structured oligonucleotide and graphene oxide keep them in close proximity, facilitating the fluorescence quenching of the fluorophore by graphene oxide. In the presence of a complementary target DNA, the binding between hairpin‐structured oligonucleotide and target DNA will disturb the interaction between hairpin‐structured oligonucleotide and graphene oxide, and release the oligonucleotide from graphene oxide, resulting in restoration of fluorophore fluorescence. In the present study, we show that this novel graphene oxide quenched molecular beacon can be used to detect target DNA with higher sensitivity and single‐base mismatch selectivity compared to the conventional molecular beacon. Honing beacons: We present a novel, highly sensitive, selective, and economical molecular beacon using graphene oxide as the “nanoquencher”. The key components of the novel graphene oxide quenched molecular beacon are the hairpin‐structured fluorophore‐labeled oligonucleotide and graphene oxide sheet, which functions as both “nanoscaffold” for the oligonucleotide and “nanoquencher” for the fluorophore (see figure).