Department of Chemistry
Medium-Dependent Antibacterial Properties and Bacterial Filtration Ability of Reduced Graphene Oxide
ORCID IDs
https://orcid.org/0000-0002-2096-4478
https://orcid.org/0000-0001-7241-6214
https://orcid.org/0000-0002-8688-3451
Document Type
Article
Date of this Version
10-13-2019
Citation
2019 by the authors.
Abstract
Toxicity of reduced graphene oxide (rGO) has been a topic of multiple studies and was shown to depend on a variety of characteristics of rGO and biological objects of interest. In this paper, we demonstrate that when studying the same dispersions of rGO and fluorescent Escherichia coli (E. coli) bacteria, the outcome of nanotoxicity experiments also depends on the type of culture medium. We show that rGO inhibits the growth of bacteria in a nutrition medium but shows little eect on the behavior of E. coli in a physiological saline solution. The observed eects of rGO on E. coli in dierent media could be at least partially rationalized through the adsorption of bacteria and nutrients on the dispersed rGO sheets, which is likely mediated via hydrogen bonding. We also found that the interaction between rGO and E. coli is medium-dependent, and in physiological saline solutions they form stable flocculate structures that were not observed in nutrition media. Furthermore, the aggregation of rGO and E. coli in saline media was observed regardless of whether the bacteria were alive or dead. Filtration of the aggregate suspensions led to nearly complete removal of bacteria from filtered liquids, which highlights the potential of rGO for the filtration and separation of biological contaminants, regardless of whether they include live or dead microorganisms.
Included in
Analytical Chemistry Commons, Medicinal-Pharmaceutical Chemistry Commons, Other Chemistry Commons
Comments
Nanomaterials 2019, 9, 1454; doi:10.3390/nano9101454 www.mdpi.com/journal/nanomaterials