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An exonuclease III and graphene oxide-aided assay for DNA detection.

ABSTRACT: We have developed a novel DNA assay based on exonuclease III (ExoIII)-induced target recycling and the fluorescence quenching ability of graphene oxide (GO). This assay consists of a linear DNA probe labeled with a fluorophore in the middle. Introduction of target sequence induces the exonuclease III catalyzed probe digestion and generation of single nucleotides. After each cycle of digestion, the target is recycled to realize the amplification. Finally, graphene oxide is added to quench the remaining probes and the signal from the resulting fluorophore labeled single nucleotides is detected. With this approach, a sub-picomolar detection limit can be achieved within 40 min at 37°C. The method was successfully applied to multicolor DNA detection and the analysis of telomerase activity in extracts from cancer cells.

SUBMITTER: Peng L

PROVIDER: S-EPMC3794672 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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An exonuclease III and graphene oxide-aided assay for DNA detection.

Peng Lu L Zhu Zhi Z Chen Yan Y Han Da D Tan Weihong W

Biosensors & bioelectronics 20120310 1

We have developed a novel DNA assay based on exonuclease III (ExoIII)-induced target recycling and the fluorescence quenching ability of graphene oxide (GO). This assay consists of a linear DNA probe labeled with a fluorophore in the middle. Introduction of target sequence induces the exonuclease III catalyzed probe digestion and generation of single nucleotides. After each cycle of digestion, the target is recycled to realize the amplification. Finally, graphene oxide is added to quench the rem ...[more]

PMID: 22464915

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