Antibacterial Performance of a Mussel-Inspired Polydopamine-Treated Ag/Graphene Nanocomposite Material

Graphene-based nanocomposites have attracted tremendous attention in recent years. In this study, a facile yet effective approach was developed to synthesize reduced graphene oxide and an Ag–graphene nanocomposite. The basic strategy involved in the preparation of reduced graphene oxide includes reducing graphene oxide with dopamine, followed by in situ syntheses of the Ag-PDA-reducing graphene oxide (RGO) nanocomposite through adding AgNO3 solution and a small amount of dopamine. The nanocomposite was characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), FTIR spectra, Raman spectra, ultraviolet-visible (UV-vis), and X-ray photoelectron spectroscopy (XPS), results indicated that a uniform PDA film is formed on the surface of the GO and GO is successfully reduced. Besides, the in situ synthesized Ag nanoparticles (AgNPs) were evenly distributed on the RGO surface. To investigate antibacterial properties Ag-PDA-RGO, different dosages were selected for evaluating the antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli. The Ag-PDA-RGO nanocomposites displayed excellent antibacterial property. The antibacterial ratio reached 99.9% against S. aureus and 90.9% against E. coli when the dosage of 100 mg/L Ag-PDA-RGO nanocomposites was 100 μL. The novel Ag-PDA-RGO nanocomposite prepared by a facile yet effective, environmentally friendly, and low-cost method holds great promise in a wide range of modern biomedical applications.

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Facile one pot microbe-mediated in situ synthesis and antibacterial activity of reduced graphene oxide-silver nanocomposite

Nanotechnology ◽

10.1088/1361-6528/ac4521 ◽

2021 ◽

Author(s):

Ashwini Patil

Keyword(s):

Antibacterial Activity ◽

Graphene Oxide ◽

Zeta Potential ◽

Reduced Graphene Oxide ◽

In Vitro Dissolution ◽

Size Analysis ◽

X Ray ◽

Reduced Graphene

Abstract The present research deals with the development of a novel bioinspired in situ fabrication of reduced graphene oxide (rGO)-silver nanoparticle (AgNPs) nanocomposite (rGO@AgNCs) using microbes namely Pseudomonas aeruginosa (PA) and Staphylococcus aureus (SA). The fabricated rGO@AgNCs were characterized using Ultraviolet-visible (UV) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), particle size analysis, polydispersity index (PDI), zeta potential analysis, energy dispersive X-ray analysis (EDAX), Raman spectroscopy, powder X-ray diffraction (PXRD), high-resolution transmission electron microscopy (HR-TEM) analysis, etc. Furthermore, the rGO@AgNCs-PA and rGO@AgNCs-SA interaction with serum protein, pH stability study, and in vitro dissolution of AgNPs were also performed. The research findings of the proposed study demonstrated the simultaneous reduction of graphene oxide (GO) and AgNPs and the formation of rGO@AgNCs in the presence of microbes. The in vitro dissolution studies of rGO@AgNCs composites showed better AgNPs dissolution with controlled release and offered remarkable matrix integrity throughout the dissolution period. The size and stability of rGO@AgNCs-PA and rGO@AgNCs-SA had no significant changes at physiological pH 7.4. A minimal decrease in the zeta potential of rGO@AgNCs was observed, which may be due to the weak interaction of nanocomposites and albumin. The antibacterial application of the synthesized nanocomposite was evaluated against a pathogenic mastitis-forming bacterium. The obtained results suggested an admirable antibacterial activity of synthesized nanocomposites against the tested microbes. This knowledge will assist the scientific fraternity in designing novel antibacterial agents with enhanced antibacterial activity against various veterinary pathogens in near future.

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Photocatalytic activity and antibacterial properties of linen fabric using reduced graphene oxide/silver nanocomposite

RSC Advances ◽

10.1039/d0ra07544b ◽

2020 ◽

Vol 10 (68) ◽

pp. 41600-41611

Author(s):

A. Farouk ◽

S. El-Sayed Saeed ◽

S. Sharaf ◽

M. M. Abd El-Hady

Keyword(s):

Silver Nanoparticles ◽

Photocatalytic Activity ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Antibacterial Properties ◽

Reduced Graphene ◽

Silver Nanocomposite ◽

Linen Fabric

Silver nanoparticles were in situ prepared on the surface of linen fabric coated by graphene oxide (GO).

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In situ X-ray powder diffraction studies of the synthesis of graphene oxide and formation of reduced graphene oxide

Journal of Solid State Chemistry ◽

10.1016/j.jssc.2016.05.019 ◽

2016 ◽

Vol 240 ◽

pp. 49-54 ◽

Cited By ~ 7

Author(s):

Mie Møller Storm ◽

Rune E. Johnsen ◽

Poul Norby

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Powder Diffraction ◽

X Ray ◽

Reduced Graphene

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Facile Fabrication of CeO2/Electrochemically Reduced Graphene Oxide Nanocomposites for Vanillin Detection in Commercial Food Products

Nanomaterials ◽

10.3390/nano10071356 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1356 ◽

Cited By ~ 2

Author(s):

Xue Nie ◽

Rui Zhang ◽

Zheng Tang ◽

Haiyan Wang ◽

Peihong Deng ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Linear Sweep Voltammetry ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Electrochemically Reduced Graphene Oxide ◽

Wide Range ◽

Facile Fabrication

In this paper, CeO2 nanoparticles were synthesized by the solvothermal method and dispersed uniformly in graphene oxide (GO) aqueous solution by ultrasonication. The homogeneous CeO2-GO dispersion was coated on the surface of a glassy carbon electrode (GCE), and the CeO2/electrochemically reduced graphene oxide modified electrode (CeO2/ERGO/GCE) was obtained by potentiostatic reduction. The results of X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) showed that CeO2 nanocrystals were uniformly coated by gossamer like ERGO nanosheets. The electrochemical behavior of vanillin on the CeO2/ERGO/GCE was studied by cyclic voltammetry (CV). It was found that the CeO2/ERGO/GCE has high electrocatalytic activity and good electrochemical performance for vanillin oxidation. Using the second derivative linear sweep voltammetry (SDLSV), the CeO2/ERGO/GCE provides a wide range of 0.04–20 µM and 20 µM–100 µM for vanillin detection, and the detection limit is estimated to be 0.01 µM after 120 s accumulation. This method has been successfully applied to the vanillin detection in some commercial foods.

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Nonenzymatic Glucose Detection in Human Serum Using Ni Nanoparticles Decorated Reduced Graphene Oxide

Science of Advanced Materials ◽

10.1166/sam.2020.3776 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1125-1136

Author(s):

Rupali Waichal ◽

Ashwini Bhirud ◽

H. Fouad ◽

Suresh Gosavi ◽

Muthupandian Ashokkumar

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Human Serum ◽

Reduced Graphene Oxide ◽

Electrocatalytic Activity ◽

Glucose Oxidation ◽

Great Promise ◽

Ni Nanoparticles ◽

X Ray ◽

Reduced Graphene

Reduced Graphene oxide (RGO) decorated with Ni nanoparticles (NiNPs) composites, have been successfully synthesized using a simple hydrothermal method and possessing excellent electrocatalytic activity towards glucose oxidation. The morphological and structural features of RGO-Ni nanocomposites were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS). From TEM, we observed that NiNPs were anchored on RGO sheets. Cyclic Voltammetric (CV) study revealed that the electrocatalytic activity of RGO-Ni nanocomposite with 20% Ni loading (RGONi-20) towards glucose oxidation is better than that shown by bare Glassy Carbon Electrode (GCE), RGO, bare NiNPs, RGONi10 and RGONi-30. The prepared nanocomposites exhibited fast electrocatalytic response (<5 s) towards glucose oxidation. Amperometric study indicates that the present glucose sensor have exhibited excellent performance by offering a lowest detection limit as 5.1 μM, with linier range from 2 to 5000 μM and high sensitivity of 896.67 μA mM–1 cm–2. Interference from different anticipatable electroactive substances such as ascorbic acid (AA), uric acid (UA) and dopamine (DA) is not observed. Furthermore, the application of the as prepared sensor was successfully demonstrated for the detection of glucose in human serum and results were compa- rable to presently used nonenzymatic technique. RGONi-20 nanocomposite electrode holds great promise for the development of biosensors and other electrochemical devices.

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A polyaniline/graphene nanocomposite prepared by in situ polymerization of polyaniline onto polyanion grafted graphene and its electrochemical properties

RSC Advances ◽

10.1039/c3ra46832a ◽

2014 ◽

Vol 4 (15) ◽

pp. 7673-7681 ◽

Cited By ~ 8

Author(s):

Tao Wu ◽

Xiaoyang Xu ◽

Lei Zhang ◽

Huabin Chen ◽

Jianping Gao ◽

...

Keyword(s):

Graphene Oxide ◽

Electrochemical Properties ◽

Hydrazine Hydrate ◽

Reduced Graphene Oxide ◽

Radical Polymerization ◽

In Situ Polymerization ◽

Reduced Graphene ◽

Graphene Nanocomposite

Poly(sodium 4-styrensulfonate), a polyanion, was grafted onto reduced graphene oxide (RGO-g-PSSNa) by in situ radical polymerization and was then chemically reduced with hydrazine hydrate.

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