Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7232897 | Biosensors and Bioelectronics | 2015 | 26 Pages |
Abstract
A novel sensitive electrochemical DNA biosensor was developed for amperometric detection of Escherichia coli O157:H7 (E. coli O157:H7). The graphene oxide (GOx) was utilized as nanocarrier to immobilize thionine (Thi) and the Au nanoparticles coated SiO2 nanocomposites (Au-SiO2) by electrostatic adsorption and the adsorption among nanomaterials. Then a large amounts of signal DNA (S2) and G-quadruplex were immobilized on the GOx-Thi-Au@SiO2 nanocomposites. Finally, hemin was intercalated into the G-quadruplex to obtain the hemin/G-quadruplex structure as HRP-mimicking DNAzyme. On the basis of the signal amplification strategy of GOx-Thi-Au@SiO2 nanocomposites and DNAzyme, the developed DNA biosensor could respond to 0.01Â nM (S/N=3) with a linear calibration range from 0.02 to 50.0Â nM E. coli O157:H7, which could be well accepted for early clinical detection. The studied system provides new opportunities, and might speed up disease diagnosis, treatment and prevention with pathogen.
Related Topics
Physical Sciences and Engineering
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Authors
Yan Li, Jun Deng, Lichao Fang, Kangkang Yu, Hui Huang, Lili Jiang, Wenbin Liang, Junsong Zheng,