The 3′–5′ exonuclease enzyme plays a dominant role in multiple pivotal physiological activities, such as DNA replication and repair processes. In this study, we designed a sensitive graphene oxide (GO)-based probe for the detection of exonuclease enzymatic activity. In the absence of Exo III, the strong π–π interaction between the fluorophore-tagged DNA and GO causes the efficient fluorescence quenching via a fluorescence resonance energy transfer (FRET). In contrast, in the presence of Exo III, the fluorophore-tagged 3′-hydroxyl termini of the DNA probe was digested by Exo III to set the fluorophore free from adsorption when GO was introduced, causing an inefficient fluorescence quenching. As a result, the fluorescence intensity of the sensor was found to be proportional to the concentration of Exo III; towards the detection of Exo III, this simple GO-based probe demonstrated a highly sensitive and selective linear response in the low detection range from 0.01 U mL −1 to 0.5 U mL −1 and with the limit of detection (LOD) of 0.001 U mL −1 . Compared with other fluorescent probes, this assay exhibited superior sensitivity and selectivity in both buffer and fetal bovine serum samples, in addition to being cost effective and having a simple setup.
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A Bioluminescent Protein‐Graphene Oxide Donor‐Quencher Pair in DNA Hybridization Assays
Despite fluorescent quenching with graphene oxide (GO) having shown great success in various applications ‐ bioluminescent quenching has not yet been demonstrated using GO as a quencher. To explore the ability of GO to quench bioluminescence, we used
- Award ID(s):
- 1841419
- NSF-PAR ID:
- 10383366
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPlusChem
- Volume:
- 87
- Issue:
- 12
- ISSN:
- 2192-6506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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