Graphene oxide-based fluorescent “turn-on” strategy for Hg2+ detection by using catalytic hairpin assembly for amplification

• Published in: Sensors and actuators. B, Chemical Vol. 249; pp. 493 - 498
• Main Authors: Yun, Wen, Xiong, Wei, Wu, Hong, Fu, Min, Huang, Yu, Liu, Xingyan, Yang, Lizhu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2017
• Subjects: Catalytic hairpin assembly; Graphene oxide; Hairpins; Hg2+ detection; Hairpins; Graphene oxide; Catalytic hairpin assembly; Hg2+ detection
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.04.134

•A novel fluorescent assay for Hg2+ detection based on graphene oxide and catalytic hairpins self-assembly have been presented.•The limit of detection was comparable or even better than enzyme-based or other enzyme-free amplification strategies.•This method provided an effective “turn-on” and sensitive approach for Hg2+ detection. We have reported an enzyme-free amplification fluorescent strategy for ultra-sensitive detection of Hg2+ based on graphene oxide (GO) and catalytic hairpins self-assembly. Three fluorophore labled metastable hairpin DNA probes can be closely adsorbed onto GO surface via π−π stacking to quench the fluorescent signal. T-Hg2+-T interaction was utilized to induce the catalytic self-assembly of hairpins with the aid of helper DNA. The formed rigid DNA triangles containing double strand DNA (dsDNA) was stiffer, and released from the surface of GO to cause a “turn-on” fluorescent signal. The limit of detection was 25 pM, which was comparable with those reported amplification strategies. This strategy showed good selectivity for Hg2+, and promising application for real samples.