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Updated: Feb 10, 2026
Visible-light Induced Reduction of Graphene Oxide Using Plasmonic Nanoparticle
Published on: September 22, 2015
Graphene oxide-assisted Au nanoparticle strip biosensor based on GR-5 DNAzyme for rapid lead ion detection
Hai-Bo Wang1, Li-Hong Ma1, Bi-Yun Fang1
1Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics, Hubei Bioinformatics & Molecular Imaging Key Laboratory, Key Laboratory of Biomedical Photonics of Ministry of Education, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China.
Abstract:
This study has reported that a GR-5 DNAzyme based lead ion strip biosensor could exhibit an enhanced specificity with the assistance of graphene oxide (GO). This enhancement results from the specific π-stacking interaction between the ribose rings of the nucleobases and the carbon hexagons in GO which can reduce the false positive interference by removing unhybridized ssDNA during the annealing of GR-5 DNAzyme. Meanwhile, conjugate pad was sprayed with two kinds of AuNP-DNA probes, and nitrocellulose membrane test zone and control zone were immobilized with two kinds of biotin-DNA probes, respectively. The limit of detection of this strip biosensor was estimated to be about 0.05 nM (S/N = 3) and 1 nM (with naked eyes) with a linear range from 0.01 to 100 μM. Furthermore, the strip biosensor exhibited excellent selectivity toward Pb2+ in the presence of other divalent metal ions. For real soil samples, the obtained recoveries were in the range from 91.5% to 113.1%.
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