Antimicrobial Features of Organic Functionalized Graphene-Oxide with Selected Amines

Abstract

(1) Background: Graphene oxide is a new carbon-based material that contains functional groups (carboxyl, hydroxyl, carbonyl, epoxy) and therefore can be easily functionalized with organic compounds of interest, yielding hybrid materials with important properties and applications. (2) Methods: Graphene oxide has been obtained by a modified Hummers method and activated by thionyl chloride in order to be covalently functionalized with amines. Thus obtained hybrid materials were characterized by infrared and Raman spectroscopy, elemental analysis and scanning electron microscopy and then tested for their antimicrobial and anti-biofilm activity. (3) Results: Eight amines of interest were used to functionalize grapheme oxide and the materials thus obtained were tested against Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacterial strainsin plankonic and biofilm growth state. Both amines, as well as the functionalized materials, exhibited anti-microbial features. Three to five functionalized graphene oxide materials exhibited improved inhibitory activity against planktonic strains as compared with the respective amines. In exchange, the amines alone proved generally more efficient against biofilm-embedded cells. (4) Conclusions: Such hybrid materials may have a wide range of potential use in biomedical applications.

Exposure of Smaller and Oxidized Graphene on Polyurethane Surface Improves its Antimicrobial Performance

“…Other strategies are being investigated, focusing on conferring anti-adhesive and/or bactericidal properties through surface modification of the medical-grade polyurethane (PU)-a thermoplastic elastomer from which most catheters are made of [9,10]. Strategies include physical and chemical modifications such as incorporation or coatings with antibiotics or antiseptics [11][12][13], topography modification with micropatterns [14], functionalization or coating with antimicrobial peptides (AMPs) [15] and antimicrobial nanomaterials, such as silver nanoparticles (Ag NPs) [16], titanium oxide (TiO 2 ) NPs [17], carbon nanotubes (CNT) [18], bioactive compounds [19], and graphene oxide (GO) [20]. Approaches that depend on eluting bactericidal agents have many drawbacks, namely the limitation of the amount loaded, difficulty in controlling the release rate and the concentration of the released agents during the application period [21,22].…”

Toxicological response of the model fungus Saccharomyces cerevisiae to different concentrations of commercial graphene nanoplatelets

“…In relation to studies investigating the biological impact of GFNs on microbial systems, many publications have reported the antibacterial properties of different graphene derivatives and composites [9][10][11][12][13] . In case of the interactions between fungi and graphene-based materials, most of the efforts have focused on improving the antifungal properties of GFNs through their modification with antimycotic drugs, peptides or metals [14][15][16][17] .…”

Comprehensive Application of Graphene: Emphasis on Biomedical Concerns

“…Several graphene composites comprising polymers (poly- l -lysine, chitosan, lactoferrin, and polyvinyl- N -carbazole) have also been developed to provide antibacterial surface for biomedical applications. Recently, Zarafu et al [ 114 ] functionalized GO with amine-containing organic compounds and investigated the antimicrobial and antibiofilm activity of Gram-negative ( Escherichia coli and Pseudomonas aeruginosa ) and Gram-positive ( S. aureus ) bacteria. These functionalized GO hybrids exhibited improved inhibitory activity against bacteria compared to amines alone.…”