Exfoliation and Decoration of Graphene Sheets with Silver Nanoparticles and Their Antibacterial Properties (original) (raw)
Related papers
Cellulose, 2022
were uniformly distributed on the surface of graphene oxide (GO) sheets with an average size of 10-15 nm, while the cotton surface was evenly covered by Ag/ rGO. The zone of inhibition against Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli) bacteria indicated that Ag/rGO/cotton possessed the highest antibacterial activity when compared to other modified cotton. Moreover, the Ag/rGO/cotton also exhibited effective hydrophobicity with a wetting angle of 103.85° ± 0.75°, which supported the prevention of bacterial infection and adherent on the cotton surface. To confirm the low cytotoxic property of Ag/rGO/cotton for human use, the cell viability of HepG2, A549, and Hek293 cell lines were evaluated when contacted with the material, while the low amount of leached Ag + from Ag/rGO/cotton was under the accepted limit. All results of the study confirmed that Ag/rGO/ cotton possesses significant potential for several antibacterial applications such as protective equipment.
Durable Antimicrobial Behaviour from Silver-Graphene Coated Medical Textile Composites
Polymers, 2019
Silver nanoparticle (AgNP) and AgNP/reduced graphene oxide (rGO) nanocomposite impregnated medical grade polyviscose textile pads were formed using a facile, surface-mediated wet chemical solution-dipping process, without further annealing. Surfaces were sequentially treated in situ with a sodium borohydride (NaBH4) reducing agent, prior to formation, deposition, and fixation of Ag nanostructures and/or rGO nanosheets throughout porous non-woven (i.e., randomly interwoven) fibrous scaffolds. There was no need for stabilising agent use. The surface morphology of the treated fabrics and the reaction mechanism were characterised by Fourier transform infrared (FTIR) spectra, ultraviolet-visible (UV–Vis) absorption spectra, X-ray diffraction (XRD), Raman spectroscopy, dynamic light scattering (DLS) energy-dispersive X-ray analysis (EDS), and scanning electron microscopic (SEM). XRD and EDS confirmed the presence of pure-phase metallic silver. Variation of reducing agent concentration all...
Materials
The resistance of microorganisms to antibiotics is a crucial problem for which the application of nanomaterials is among a growing number of solutions. The aim of the study was to create a nanocomposite (composed of graphene oxide and silver nanoparticles) with a precise mode of antibacterial action: what enables textiles to be coated in order to exhibit antibacterial properties. A characterization of nanomaterials (silver nanoparticles and graphene oxide) by size distribution, zeta potential measurements, TEM visualization and FT-IR was performed. The biological studies of the nanocomposite and its components included the toxicity effect toward two pathogenic bacteria species, namely Pseudomonas aeruginosa and Staphylococcus aureus, interaction of nanomaterials with the outer layer of microorganisms, and the generation of reactive oxygen species and lipid peroxidation. Afterwards, antibacterial studies of the nanocomposite’s coated textiles (cotton, interlining fabric, polypropylen...
Graphene Oxide-Based Nanocomposites Decorated with Silver Nanoparticles as an Antibacterial Agent
Nanoscale research letters, 2018
One of the most promising methods against drug-resistant bacteria can be surface-modified materials with biocidal nanoparticles and nanocomposites. Herein, we present a nanocomposite with silver nanoparticles (Ag-NPs) on the surface of graphene oxide (GO) as a novel multifunctional antibacterial and antifungal material. Ultrasonic technologies have been used as an effective method of coating polyurethane foils. Toxicity on gram-negative bacteria (Escherichia coli), gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), and pathogenic yeast (Candida albicans) was evaluated by analysis of cell morphology, assessment of cell viability using the PrestoBlue assay, analysis of cell membrane integrity using the lactate dehydrogenase assay, and reactive oxygen species production. Compared to Ag-NPs and GO, which have been widely used as antibacterial agents, our nanocomposite shows much higher antimicrobial efficiency toward bacteria and yeast cells.
Nanomaterials
Nanocomposites obtained by the decoration of graphene-based materials with silver nanoparticles (AgNPs) have received increasing attention owing to their antimicrobial activity. However, the complex synthetic methods for their preparation have limited practical applications. This study aims to synthesize novel NanoHybrid Systems based on graphene, polymer, and AgNPs (namely, NanoHy-GPS) through an easy microwave irradiation approach free of reductants and surfactants. The polymer plays a crucial role, as it assures the coating layer/substrate compatibility making the platform easily adaptable for a specific substrate. AgNPs’ loading (from 5% to 87%) can be tuned by the amount of Silver salt used during the microwave-assisted reaction, obtaining spherical AgNPs with average sizes of 5–12 nm homogeneously distributed on a polymer-graphene nanosystem. Interestingly, microwave irradiation partially restored the graphene sp2 network without damage of ester bonds. The structure, morpholog...
Journal of Applied Polymer Science, 2022
Herein, poly(propylene) (PP) was hydrophilized with oxidating agents and solvents , followed by dip-coating with silver nanoparticles anchored GO sheets (Ag@GO) prepared by the in-situ method as reported in our previous study to obtain silver@graphene oxide-coated poly(propylene) (Ag@GO/PP). The impact of the modifying agents, dipping times, and coating concentrations on the antibacterial activities were studied accordingly via the inhibition zone method. The fabrics were re-hydrophobized with the reduction of Ag@GO and the functionalization with stearic acid (SA) to form silver@reduced graphene oxide-coated poly(propylene) (Ag@rGO/PP) and silver@graphene oxide/SA-coated poly(propylene) (Ag@rGO-SA/PP), respectively. Characterization of pretreated and modified PP samples was carried out by various modern analysis methods. Simultaneously, the cytotoxicity of the active layers, the release of Ag + ions, and durability after washing were also investigated. The obtained results representing PP fabrics pretreated with HNO 3 /isopropanol and dipped in Ag@GO concentration of 2 g/L four times prove a sufficient approach for improving hydrophilization and bio-compatibility for the PP samples. The fabrics greatly show an impressive interaction with precursors, mostly high anti-bacterial activity even after four washing cycles via appropriate releasing of Ag + to ensure the safety in usage. They further suggest that the prepared fabrics could be utilized for actual application as a face mask.
Micromachines
Recently, there has been much attention paid to functionalized few-layer graphene (FFG) owing to its many biomedical applications, such as in bioimaging, biosensors, drug delivery, tissue scaffolds, nanocarriers, etc. Hence, the preparation of FFG has now become of great interest to researchers. The present study systematically investigates the utilization of gallnut extract (GNE) during the process of high-shear exfoliation for the efficient conversion of expanded graphite to FFG. Various parameters, such as GNE concentration, graphite concentration, exfoliation time, and the rotation speed of the high-shear mixer, were initially optimized for FFG production. The prepared FFG was characterized in terms of surface functionality and morphology using Raman spectra, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy, and scanning electron microscopy analyses. Further, the conjugation of FFG with Ag was confirmed by XRD, XPS, and energy-dis...
A new route for the synthesis of aminophenol grafted and Ag NPs decorated reduced graphene sheet (Ag-RGS) was developed as an effective antibacterial nanostructure. The nucleophilic substitution reaction of amine group of aminophenol with epoxy group of GO in the presence of silver nitrate and subsequent reduction with hydrazine generated Ag-RGS nanocomposite. The morphology and structure of the as-synthesized nanocomposite was characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy. TEM images of Ag-RGS revealed that the silver nanoparticles were decorated on the surface of the graphene sheet. The presence of phenolic groups and silver nanoparticles on the surface of Ag-RGS showed synergistic effect on antibacterial activity against Escherichia coli and Staphylococcus aureus. This feature of the Ag-RGS nanocomposite showed that it can be a promising candidate in broad range of antibiotics.
Matéria (Rio de Janeiro)
The rise of nanotechnology has allowed the development of several inorganic nanoparticles with strong biocidal properties against bacteria, fungi, and viruses. Among them, silver nanoparticles (AgNPs) stand out as one of the most promising antimicrobial nanomaterials. Graphene oxide (GO) is another attractive nanomaterial with antimicrobial properties. Although the antimicrobial effect of AgNPs and GO is known, the development of hybrid materials of GO-AgNPs has considerable interest in various applications since they may exhibit synergistic bactericidal properties that exceed the yields of the individual components. The aims of this work were to evaluate the antimicrobial activity and anti-adhesion properties of AgNPs and GO-AgNPs nanocomposites for potential applications in antimicrobial coatings. The antimicrobial activity was tested by agar diffusion method. It was found that activity varied according to the synthesis procedure of the nanomaterials. Pseudomonas aeruginosa, Bacillus cereus and Kokuria rhizophila were the most susceptible strains. The nanocomposite GO-AgNPs synthetized using the ex-situ method exhibited the highest antibacterial activity against all the assayed strains. Similar results were obtained for bacterial adhesion inhibition tests. Thus, GO-AgNPs nanohybrids could be applied as antibacterial coatings to prevent bacterial biofilm development.
Materials Technology, 2018
A stable composite material of graphene-silver nanocomposite is synthesized using amla leaf extract as reducing as well as stabilizing agent from its precursor solution of graphene oxide and silver ions. The composite is investigated using UV-Vis, FT-IR and Raman spectroscopic techniques that confirmed the formation of said nanocomposite and further characterized by the The X-ray diffraction studies. The average size of silver nanoparticles (Ag NPs) is calculated to be 28 nm. The high resolution scanning electron microscope investigations also confirmed the formation of graphene sheets and the distribution of Ag NPs on these sheets. The graphene-silver nanocomposite exhibited good antimicrobial efficiency against two gram negative (Xanthomonascampestris, Escherichia coli), and two gram positive bacterial(Bacillus megaterium, Candida albicans) cultures.