Oxide-silver Nanocomposite Research Articles

Eco-friendly Synthesis of Silver-Doped Reduced Graphene Oxide Nanocomposite, The Characterization, and Evaluation of Electrochemical Activity

In this study, Orobanche aegyptiaca Pers., which is an important holoparasite plant, was used for green synthesis of reduced graphene oxide silver nanocomposites (rGO-AgNCs). The obtained rGO-AgNCs were characterizated using UV–Vis spectroscopy, Fourier transformation infrared spectroscopy (FT-IR), X-Ray diffractiometer (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM), and X-Ray photoelectron spectroscopy (XPS). The synthesized rGO-AgNCs structure were used to modify carbon paste electrode (rGO-AgNCs@CPE) for electrochemical determination of metronidazole (MNZ). It was observed that the obtained rGO-AgNCs@CPE showed higher sensitivity in MNZ determination than the unmodified CPE, and DPV measurements showed a low detection limit of 0.039 μM over a linear concentration range of 5–300 μM. Real sample analysis of the proposed sensor shows that it responds well in MNZ analysis of human urine.

Antiviral Activity of Graphene Oxide-Silver Nanocomposites Against Murine Betacoronavirus.

The high infectivity of coronaviruses has led to increased interest in developing new strategies to prevent virus spread. Silver nanoparticles (AgNPs) and graphene oxide (GO) have attracted much attention in the antiviral field. We investigated the potential antiviral activity of GO and AgNPs combined in the nanocomposite GO-Ag against murine betacoronavirus MHV using an in vitro model. GO, AgNPs, and GO-Ag characterization (size distribution, zeta potential, TEM visualization, FT-IR, and EDX analysis) and XTT assay were performed. The antiviral activity of GO-Ag nanocomposites was evaluated by RT-qPCR and TCID50 assays. The results were compared with free AgNPs and pure GO. Cell growth and morphology of MHV-infected hepatocytes treated with GO-Ag composites were analyzed by JuLI™Br. Immunofluorescence was used to visualize the cell receptor used by MHV. Ultrastructural SEM analysis was performed to examine cell morphology after MHV infection and GO-Ag composite treatment. A significant reduction in virus titer was observed for all nanocomposites tested, ranging from 3.2 to 7.3 log10 TCID50. The highest titer reduction was obtained for GO 5 µg/mL - Ag 25 µg/mL in the post-treatment method. These results were confirmed by RT-qPCR analysis. The results indicate that GO-Ag nanocomposites exhibited better antiviral activity compared to AgNPs and GO. Moreover, the attachment of AgNPs to the GO flake platform reduced their cytotoxicity. In addition, the GO-Ag composite modulates the distribution of the Ceacam1 cell receptor and can modulate cell morphology. Graphene oxide sheets act as a stabilizing agent, inhibiting the accumulation of AgNPs and reducing their cellular toxicity. The GO-Ag composite can physically bind and inhibit murine betacoronavirus from entering cells. Furthermore, the constant presence of GO-Ag can inhibit MHV replication and significantly limit its extracellular release. In conclusion, GO-Ag shows promise as an antiviral coating on solid surfaces to minimize virus transmission and spread.

Enhanced anticancer activity of silver doped zinc oxide magnetic nanocarrier loaded with sorafenib for hepatocellular carcinoma treatment

Drug delivery is the process or method of delivering a pharmacological product to have therapeutic effects on humans or animals. The use of nanoparticles to deliver medications to cells is driving the present surge in interest in improving human health. Green nanodrug delivery methods are based on chemical processes that are acceptable for the environment or that use natural biomaterials such as plant extracts and microorganisms. In this study, zinc oxide-superparamagnetic iron oxide-silver nanocomposite was synthesized via green synthesis method using Fusarium oxysporum fungi mycelia then loaded with sorafenib drug. The synthesized nanocomposites were characterized by UV-visibile spectroscopy, FTIR, TEM and SEM techniques. Sorafenib is a cancer treatment and is also known by its brand name, Nexavar. Sorafenib is the only systemic medication available in the world to treat hepatocellular carcinoma. Sorafenib, like many other chemotherapeutics, has side effects that restrict its effectiveness, including toxicity, nausea, mucositis, hypertension, alopecia, and hand-foot skin reaction. In our study, 40 male albino rats were given a single dose of diethyl nitrosamine (DEN) 60 mg/kg b.wt., followed by carbon tetrachloride 2 ml/kg b.wt. twice a week for one month. The aim of our study is using the zinc oxide-superparamagnetic iron oxide-silver nanocomposite that was synthesized by Fusarium oxysporum fungi mycelia as nanocarrier for enhancement the sorafenib anticancer effect.

Rocephin-graphene oxide-silver nanocomposites: A versatile platform for biomedical applications.

For many years, the synthesis of graphene oxide (GO) had involved exfoliating graphite flakes, and the methods applied were expensive and time-consuming. Thus, an attempt had been made to create an inventive, less expensive method for the synthesis of GO using unrefined, raw carbon-containing material. Modified Hummer's method was used to prepare GO from banana peel. In addition, the metallic silver nanocomposite was also synthesized along with laoding of drug Rocephin where they interact with each other through electrostatic hydrogen bond interaction. The degree of crystallinity and the crystallite size were through x-ray diffraction (XRD) analysis and the crystallite size of AgNPs was found to be 40.40 nm. The scanning electron microscopy (SEM) analysis shows that the morphology of the GO gradually changes with the addition of AgNPs and Rocephin. A blue shift was seen in the absorbance maxima of the raw carbon upon the conjugation of Rocephin in UV analysis. The Fourier-transform infrared spectroscopy, and energy dispersive X-ray (EDX) spectroscopy were used to determine the chemical composition of the samples. Furthermore, a broad biological screening of the synthesized samples had been carried out following the total reducing power (TRP), total antioxidant capacity (TAC), antibacterial, antifungal, MTT (Cytotoxicity of biologically synthesized silver nanoparticles in MDA-MB-231 human breast cancer cells) cell viability, brine shrimp lethality, and hemolytic protocols. Significant results were obtained, and the Rocephin-GO-AgNPs had depicted promising activity as compared with their counterparts. RESEARCH HIGHLIGHTS: The GO was prepared from the raw carbon extracted from banana peels and was used as a substrate for the synthesis Graphene oxide silver nanoparticles (GO-AgNPs) and Rocephin-loaded graphene oxide silver nanoparticles (Rocephin-GO-AgNPs) The structural and compositional analysis of the nanomaterial was carried out, and they were screened for several biomedical applications. The Rocephin-GO-AgNPs exhibit the highest activity as compared with their counterparts.

SAR Flexible Antenna Advancements: Highly Conductive Polymer-graphene Oxide-silver Nanocomposites

SAR Flexible Antenna Advancements: Highly Conductive Polymer-graphene Oxide-silver Nanocomposites

Squeezing motion of radiative magnetized ternary hybrid nanofluid containing graphene-graphene oxide-silver nanocomposite in water base fluid placed between two parallel plates

The present article explores flow of ternary hybrid nanofluid (THN) between two parallel plates in which upper one is in squeezing motion. The study of squeezing flow has its importance in industrial applications, like the flow between pistons and nozzles in the engine of vehicles. THN (graphene-graphene oxide-silver/water) is used to improve the efficiency of heat carrier fluid by the synergetic effects of nanoparticles. Magnetic field and thermal radiation effects are also included in the problem. Governing mathematical form of the problem is constructed by using a modified Buongiorno nanofluid model. Dimensionless system of ODEs reduced from PDEs through transformations and further simplified towards the solution with the numerical approach ‘bvp4c’, a MATLAB based solver. The reliability of the outcomes is confirmed by matching them with the previously published works. The findings reveal that the nanofluid velocity reduces with squeezing and magnetic parameters in the mid-section between the plates and its temperature can be controlled by the amount of nanoparticles dispersed into it, Prandtl number and the radiation effect. Overshoot in the concentration is attained for higher temperature gradient forces. Also, local Nusselt and local Sherwood numbers show contrasting trends for the upper and lower plates with the types of nanofluid (ternary/binary/unary), Prandtl number and radiation effect, but remain stationary with compression and magnetic effect. That means better transfer characteristics are found for ternary nanofluid, radiation and magnetic effects for the lower plate, but drag also intensifies; so suitable choices are considered for practical purposes. By the comparative analysis, it can be concluded that the performance of ternary hybrid nanofluid is relatively more efficient than binary and unary for heat transfer applications.

Identification of circular RNAs expression pattern in caprine fetal fibroblast cells exposed to a chronic non-cytotoxic dose of graphene oxide-silver nanoparticle nanocomposites.

The widespread use of graphene oxide-silver nanoparticle nanocomposites (GO-AgNPs) in biomedical sciences is increasing the chances of human and animal exposure to its chronic non-toxic doses. Exposure to AgNPs-related nanomaterials may result in the negative effect on the dam, fetus and offspring. However, there are only little available information for profound understanding of the epigenetic alteration in the cells and animals caused by low-dose chronic exposure of GO-AgNPs. The present study investigated the effect of 0.5μg/mL GO-AgNPs for 10weeks on the differential expression of circular RNAs (circRNAs) in caprine fetal fibroblast cells (CFFCs), and this dose of GO-AgNPs did not affect cell viability and ROS level. We predicted the functions of those differentially expressed (DE) circRNAs in CFFCs by bioinformatics analysis. Furthermore, we validated the expression of ten DE circRNAs using quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) to ensure the reliability of the sequencing data. Our results showed that the DE circRNAs may potentially regulate the GO-AgNPs-inducing epigenetic toxicity through a regulatory network consisted of circRNAs, miRNAs and messenger RNAs (mRNAs). Therefore, the epigenetics toxicity is essential to assess the biosafety level of GO-AgNPs.

Characterization of Chitosan-Titanium Oxide-Silver Nanocomposite Synthesized by Pulsed Laser Ablation in Liquid

Chitosan-titanium oxide-silver CS-TiO2 -Ag nanocomposite was successfully synthesized using pulsed laser ablation in liquid with a frequency of 1 Hz and energy of 500 mJ, and the number of pulses of titanium and silver plates was 1000 and 500, respectively. The resulting nanocomposite was characterized using various techniques, including FTIR, UV-vis, X-ray diffraction, and SEM. The FTIR analysis showed that the chemical bonds of chitosan were superimposed with silver and titanium oxide. UV-vis spectrum showed that the absorbance peaks for CS-Ag and CS-TiO2 at 399.9 nm and 242 nm, respectively, and the calculating energy gaps of the CS-TiO2 ,CS-Ag and CS-TiO2 -Ag nanocomposites are found to be (4.18 , 2.82 and 2.74 ) eV, respectively. The SEM images for CS-TiO2 -Ag showed that the shape as semi-spherical, and the average grain size of the nanoparticles is 95 nm. Moreover, the X-ray diffraction analysis revealed that TiO2 and Ag were polycrystalline and that the average crystallite sizes for CS-Ag, CS-TiO2 , and CS-TiO2 -Ag were 5.96, 5.96, and 5.95 nm, respectively. This study demonstrated that pulsed laser ablation in liquid is an easy and safe method for synthesizing CS-TiO2 -Ag nanocomposites that can be used in various applications. The characterization techniques used in this study provided valuable insights into the properties and structures of the synthesized nanocomposite material.

Preparation, characterization, and biological assessment of functionalized reduced graphene oxide–silver nanocomposite

In this work, functionalized reduced graphene oxide–silver (FrGO–Ag) nanocomposite was synthesized to enhance the antimicrobial activity and biocompatibility of FrGO for infected wound burn treatment. The reduction of GO and FGO was confirmed by the removal of some of the oxygen functional groups (carbonyl and epoxy groups) as revealed by Fourier transform infrared (FTIR) spectra. The face-centered cubic (fcc) silver nanoparticles were identified by X-ray diffraction (XRD). The contact time effect and the dose effect of the antimicrobial activity of rGO, FrGO, and FrGO-Ag nanocomposite toward Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans have been investigated. The cytotoxicity results of these compounds revealed that the functionalization by PVP and the decoration by AgNPs improved the biocompatibility of rGO sheets from 35.2 to 88% cell viability against the BJ1 normal human epithelial cell line.Graphical

Preparation of poly(ε-caprolactone) nanofibrous mats incorporating graphene oxide-silver nanoparticle hybrid composite by electrospinning method for potential antibacterial applications

In this study, poly(ε-caprolactone) based fibrous mats incorporating graphene oxide-silver hybrid nanocomposite as a nanofiller were successfully prepared by electrospinning method for potential biomedical applications. First, graphene oxide-silver nanoparticles (GO-AgNPs) were synthesized and the obtained GO-AgNPs nanohybrid was characterized by different analytical techniques. It was observed that the obtained AgNPs, with an average size of 5 ± 0.5 nm and spherical shape, were uniformly anchored on the surface of GO. Then, the synthesized GO-AgNPs were added into PCL to improve its tensile and bactericidal performances. The structural, morphological, mechanical and wettability properties of PCL-based fibrous mats as well as the release of silver ion release from PCL matrix were examined. Based on the results, we found that the addition of GO to the PCL-3.0%Ag nanofibers resulted in increased hydrophilicity, tensile strength and resistance to elastic deformation, and the PCL-GO-3.0%Ag sample also had a significantly higher release of silver ions. Besides, PCL-GO–3.0%Ag mats showed good antibacterial activity against Staphylococcus aureus and Escherichia coli compared to the PCL, PCL-GO and PCL-Ag nanofibrous mats. In summary, this study showed that PCL-GO–3.0%Ag nanofibrous mats could be a promising biomaterial for potential antibacterial applications.

Controlled cytotoxicity of Ag-GO nanocomposite biosynthesized using black peel pomegranate extract against MCF-7 cell line

The lack of definitive treatment for cancer and the emergence of drug-resistant cancers highlights the need for alternative therapies and effective anti-cancer agents. Here, we developed and applied a green approach to fabricate Silver nanoparticles (AgNPs) and Graphene oxide-Silver nanocomposite (Ag-GO) using the black peel pomegranate extract. The nanomaterials' physicochemical properties were characterized using UV–Visible, FTIR, TEM-EDX, and Zeta potential analyses. Then, the nanomaterials' biological activities against cancerous (MCF-7) and normal (HUVEC) cells were evaluated via MTT assay, real-time PCR, and ROS/DCFDA assay protocols. Based on the results, synthesized AgNPs were spherical with 35 ± 5 nm diameter and adequate dispersity. However, very small and uniform AgNPs (10 ± 2 nm) with great dispersity were formed on the GO surface. Also, the nanocomposite surface charge (−41 mV) was substantially lower than that of AgNPs (−28 mV), indicating higher stability. Both AgNPs and Ag-GO showed much more activity against cancerous cells than normal ones. Yet, AgNPs cytotoxicity was severe, so that 500 μg/ml of this compound, independently of time, reduced the viability of HUVEC and MCF-7 cells to about 41% and 20%, respectively. Ideally, the Ag-GO activity was moderate and time-dependent. 24 h exposure of MCF-7 cells to this compound (500 μg/ml) led to the increase of cell death from 30% to more than 50% after 48 h. Both nanocompounds increased the Bax/Bcl-2 ratio and intracellular ROS, though, AgNPs showed the most activity to increase the Bax/Bcl-2 ratio, while Ag-GO more effectively increased the amount of ROS levels. These findings demonstrated the method's capability of synthesizing nanocomposites with desirable physicochemical and biological properties.

Polycaprolactone/Graphene Oxide–Silver Nanocomposite: A Multifunctional Agent for Biomedical Applications

Polycaprolactone/Graphene Oxide–Silver Nanocomposite: A Multifunctional Agent for Biomedical Applications

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

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–Vis) 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.

Photocatalytic degradation of Janus Green Blue dye in wastewater by green synthesised reduced graphene oxide-silver nanocomposite

ABSTRACT In this study, green synthesis of reduced graphene oxide-Ag (rGO-Ag) nanocomposite was carried out via bioreduction of Ag salt and graphene oxide (GO) using waste dry cell battery rod and Corchorus olitorius extract as GO precursor and reducing agent, respectively. Characterisation of rGO-Ag nanocomposite was achieved by UV/Vis spectroscopy, XRD, SEM, FTIR and BET analyses. Photocatalytic degradation of Janus Green blue (JGB) dye was conducted in batch mode. Effects of irradiation time, photocatalyst composition, temperature and recyclability were investigated. BET surface area of the nanocomposite was 532.914 m2/g with pore size of 2.136 nm. Optimal percentage photo-removal and equilibrium adsorption capacity of JGB dye by the nanocomposite achieved were 95.72% and 120.48 mg/g, respectively. Photocatalytic adsorption process followed more accurately Freundlich model implying multilayer adsorption onto rGO-Ag surface. Adsorption kinetics fitted perfectly into pseudo-second-order model while the enthalpy change is endothermic. The photocatalyst exhibited considerable stability, efficiency and was successfully applied for the removal of JGB in wastewater samples.

Bifunctional manganese oxide–silver nanocomposites anchored on graphitic mesoporous carbon to promote oxygen reduction and inhibit cathodic biofilm growth for long-term operation of microbial fuel cells fed with sewage

Manganese oxide–silver nanocomposites anchored on graphitic mesoporous carbon were synthesized for enhancing oxygen reduction and inhibiting cathodic biofilm growth for the long-term operation of microbial fuel cells.

Correction: Bifunctional manganese oxide–silver nanocomposites anchored on graphitic mesoporous carbon to promote oxygen reduction and inhibit cathodic biofilm growth for long-term operation of microbial fuel cells fed with sewage

Correction for ‘Bifunctional manganese oxide–silver nanocomposites anchored on graphitic mesoporous carbon to promote oxygen reduction and inhibit cathodic biofilm growth for long-term operation of microbial fuel cells fed with sewage’ by Dena Z. Khater et al., Sustainable Energy Fuels, 2022, DOI: 10.1039/d1se01479j.

Synthesis, characterization, and comparative assessment of antimicrobial properties and cytotoxicity of graphene-, silver-, and zinc-based nanomaterials.

Zinc oxide (ZnO) and graphene oxide (GO) nanoparticles, silver/zinc zeolite (Ag/Zn-Ze), and graphene oxide-silver (GO-Ag) nanocomposites were synthesized and characterized with X-ray powder Diffraction, Field Emission Scanning Electron Microscope and Fourier Transform-Infrared Spectroscopy. The antibacterial efficacy of these nanoparticles was evaluated against E. coli. by shake flask method and plate culture method for different concentrations. For 105 cells/mL initial bacterial concentration, minimum inhibitory concentration (MIC) were<160,<320,<320, and>1280μg/mL, and antibacterial concentration at which 50% cells are inhibited (IC50) were 47, 90, 78, and 250μg/mL for Ag/Zn-Ze, GO, GO-Ag, and ZnO, respectively. Therefore, the shake flask method showed that for all nanoparticle concentrations, Ag/Zn-Ze, and GO-Ag exhibited greater inhibition efficacy, which was also highly dependent on initial bacterial concentration. However, in case of the plate culture method, similar range of inhibition capacity was found for Ag/Zn-Ze, GO-Ag, and ZnO, whereas GO showed lower potency to inhibit E. coli. In addition, GO-Ag nanocomposite exhibited more efficacy than Ag/Zn-Ze when the antibacterial surface was prepared with those. However, Ag/Zn-Ze showed no toxicity on Vero cells, whereas GO-Ag exhibited severe toxicity at higher concentrations. This study establishes GO-Ag and Ag/Zn-Ze as potent antimicrobial agents; however, their application dosage should carefully be chosen based on cytotoxic effects of GO-Ag in case of any possible physiological interaction.

Multifunctional Magnesium Organic Framework-Based Microneedle Patch for Accelerating Diabetic Wound Healing.

Diabetic wound healing is one of the major challenges in the biomedical fields. The conventional single drug treatments have unsatisfactory efficacy, and the drug delivery effectiveness is restricted by the penetration depth. Herein, we develop a magnesium organic framework-based microneedle patch (denoted as MN-MOF-GO-Ag) that can realize transdermal delivery and combination therapy for diabetic wound healing. Multifunctional magnesium organic frameworks (Mg-MOFs) are mixed with poly(γ-glutamic acid) (γ-PGA) hydrogel and loaded into the tips of MN-MOF-GO-Ag, which slowly releases Mg2+ and gallic acid in the deep layer of the dermis. The released Mg2+ induces cell migration and endothelial tubulogenesis, while gallic acid, a reactive oxygen species-scavenger, promotes antioxidation. Besides, the backing layer of MN-MOF-GO-Ag is made of γ-PGA hydrogel and graphene oxide-silver nanocomposites (GO-Ag) which further enables excellent antibacterial effects for accelerating wound healing. The therapeutic effects of MN-MOF-GO-Ag on wound healing are demonstrated with the full-thickness cutaneous wounds of a diabetic mouse model. The significant improvement of wound healing is achieved for mice treated with MN-MOF-GO-Ag.

UV-Irradiation synthesized α-Fe2O3 nanoparticles based dye-sensitized solar cells

Nanoparticles are commonly used in various fields, including environmental science, analytical chemistry, agriculture, medicine, and energy. This is because of the unique properties of NPs and the innovation they provide to such applications. Because of their physical properties and technological potential, nanoparticles have gotten a lot of attention. In this study, iron oxide nanoparticles (α-Fe2O3 NPs) via a photolysis process utilizing UV lamb are described. The Nano-powder was studied using transmittance electron microscopy (TEM), X-ray diffraction (XRD), Energy Dispersive X-Ray Analysis (EDX), photoluminescence spectroscopy(PL), and field emission scanning electron microscope (FE-SEM). The particles size of the α-Fe2O3 NPs was to be 25 nm confirmed by FE-SEM. The X-ray diffraction analysis indicated no impurity peaks. PL spectroscopy was used to analyze the optical properties, and the energy gap was reported to be 2.49 eV. The broad bandgap is a semiconductor property that could be used in solar cell applications. We employed photochemically produced α-Fe2O3 NPs as a photo-anode in dye-sensitized solar cells. As counter electrodes, graphene oxide (GO) Nano-Sheets and graphene oxide-silver (GO-Ag) nanocomposite were used in this study. Cibacron brilliant red B is one of the colors utilized in the textile sector in Wasit Governorate. The rest is usually released as wastewater, which we used as a photosensitizer in our studies. The short-current density (Jsc), open-circuit voltage (Voc), efficiency (ɳ), and fill factor (FF) were measured using J-V curves, with efficiency ranging from 0.810 to 2.13 %. Eventually, the inclusion of Iron oxide nanoparticles combined with a cibacron brilliant red B dye has been shown to improve the performance of dye-sensitized solar cells.

Antiproliferative activity of zinc oxide-silver nanocomposite interlinked with Vaccinium arctostaphylos L. fruit extract against cancer cells and bacteria

Antiproliferative activity of zinc oxide-silver nanocomposite interlinked with Vaccinium arctostaphylos L. fruit extract against cancer cells and bacteria