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Design and engineering of graphene-based functional nanomaterials for effective antimicrobial applications has been attracting extensive interest. In the present study, graphene oxide quantum dots (GOQDs) were prepared by chemical exfoliation of carbon fibers and exhibited apparent antimicrobial activity. Transmission electron microscopic measurements showed that the lateral length ranged from a few tens to a few hundred nanometers. Upon reduction by sodium borohydride, whereas the UV-vis absorption profile remained largely unchanged, steady-state photoluminescence measurements exhibited a marked blue-shift and increase in intensity of the emission, due to (partial) removal of phenanthroline-like structural defects within the carbon skeletons. Consistent results were obtained in Raman and time-resolved photoluminescence measurements. Interestingly, the samples exhibited apparent, but clearly different, antimicrobial activity against Staphylococcus epidermidis cells. In the dark and under photoirradiation (400 nm), the as-produced GOQDs exhibited markedly higher cytotoxicity than the chemically reduced counterparts, likely because of (i) effective removal by NaBH 4 reduction of redox-active phenanthroline-like moieties that interacted with the electron-transport chain of the bacterial cells, and (ii) diminished production of hydroxyl radicals that were potent bactericidal agents after chemical reduction as a result of increased conjugation within the carbon skeletons.
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Graphene Oxide Quantum Dot‐Based Functional Nanomaterials for Effective Antimicrobial Applications
Abstract Conventional β‐lactam antibiotics are resisted by bacteria at an increasing rate, prompting studies into the development of alternate antibiotic agents. In this personal account, we summarize recent progress in the design and engineering of graphene oxide quantum dot‐based nanomaterials as potent antimicrobial agents. Specifically, we examine the impacts of chemical reduction on the antimicrobial activity of graphene oxide quantum dots, and enhancement of the bactericidal performance by the formation of nanocomposites with metal oxide nanoparticles, within the context of photodynamic generation of reactive oxygen species. A perspective is also included where the promises and challenges are highlighted in the development of high‐performance antimicrobial agents based on graphene derivatives.
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- Award ID(s):
- 1848841
- PAR ID:
- 10258987
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- The Chemical Record
- Volume:
- 20
- Issue:
- 12
- ISSN:
- 1527-8999
- Page Range / eLocation ID:
- p. 1505-1515
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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