The industry of nanotechnology has had a rapid development in the last decades. In particular, silver nanoparticles (AgNPs) have unique properties so they can be used in different industrial ...applications, mainly in areas such as electronics, environment, medicine, biosensors and biotechnology; as well as household and healthcare‐related products, like cosmetics, due to their antimicrobial properties. These beneficial effects are also offset by the higher chemical reactivity of these NPs due to their surface area to volume ratio, leading to the increased formation of reactive oxygen species (ROS) within cells. AgNPs, however, have a dark side: they increase the formation of reactive oxygen species (ROS). With increased human exposure to AgNPs, the risk and safety standards have attracted much attention. This review highlights the beneficial and toxicological effects of AgNPs in terms of cytotoxicity and genotoxicity.
The positive side of silver nanoparticles (AgNPs) allows them to be used in various applications; however, its negative side is associated with the formation of reactive oxygen species (ROS).
Multidrug resistance of the pathogenic microorganisms to the antimicrobial drugs has become a major impediment toward successful diagnosis and management of infectious diseases. Recent advancements ...in nanotechnology-based medicines have opened new horizons for combating multidrug resistance in microorganisms. In particular, the use of silver nanoparticles (AgNPs) as a potent antibacterial agent has received much attention. The most critical physico-chemical parameters that affect the antimicrobial potential of AgNPs include size, shape, surface charge, concentration and colloidal state. AgNPs exhibits their antimicrobial potential through multifaceted mechanisms. AgNPs adhesion to microbial cells, penetration inside the cells, ROS and free radical generation, and modulation of microbial signal transduction pathways have been recognized as the most prominent modes of antimicrobial action. On the other side, AgNPs exposure to human cells induces cytotoxicity, genotoxicity, and inflammatory response in human cells in a cell-type dependent manner. This has raised concerns regarding use of AgNPs in therapeutics and drug delivery. We have summarized the emerging endeavors that address current challenges in relation to safe use of AgNPs in therapeutics and drug delivery platforms. Based on research done so far, we believe that AgNPs can be engineered so as to increase their efficacy, stability, specificity, biosafety and biocompatibility. In this regard, three perspectives research directions have been suggested that include (1) synthesizing AgNPs with controlled physico-chemical properties, (2) examining microbial development of resistance toward AgNPs, and (3) ascertaining the susceptibility of cytoxicity, genotoxicity, and inflammatory response to human cells upon AgNPs exposure.
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•Multifunctional fabrics was achieved by coating with AgNPs and polymers.•The EMI SE of the composite fabrics could reach ~112 dB.•The composite fabrics exhibited superhydrophobic ...performance.•The composite fabrics have good anti-corrosion and self-cleaning ability.•The composite fabrics had good antibacterial ability.
Multifunctional cotton fabrics have attracted significant attention as next-generation wearable materials. Herein, we report a facile method for the fabrication of flexible and wearable cotton fabrics with ultra-high electromagnetic interference (EMI) shielding, antibacterial, and superhydrophobic properties. Cotton fabrics were first coated chemically with silver nanoparticles using polydopamine as adhesive and then with hydrophobic polydimethylsiloxane or polyimide. The introduction of polydopamine significantly increased the bond between silver nanoparticles and cotton fibers, thereby preventing silver nanoparticles from falling off the surface. The composite fabrics exhibited a high conductivity of ~1000 S/cm, and their EMI shielding effectiveness increased up to ~110 dB. The composite fabrics exhibited excellent self-cleaning performance and acid-alkali corrosion resistance because of their superhydrophobicity. Notably, the fabric composites showed a significant antibacterial action against Staphylococcus aureus and Escherichia coli.
Non-healing wounds are among the serious complications of type-2-diabetes around the globe, associated with high incidence of bacterial infection, chronic nerve and blood vessel damage, and ...eventually repeated amputation of limbs and organs. Silver nanoparticles offer strong wound healing potential due to their well-known antibacterial activities. The present study reports the development of silver nanoparticle impregnated chitosan-poly ethylene glycol (PEG) hydrogel to accelerate wound healing in diabetic patients. The aim of the study was to formulate a sustained and slow release of silver nanoparticle using chitosan-PEG-Silver Nitrate based hydrogel for the treatment of chronic diabetic wounds. The silver nanoparticle containing chitosan-PEG pre-polymer solution was synthesized by reducing silver nitrate with PEG and chitosan solution, thereby, transforming the silver ions into silver nanoparticles. The resulted pre-polymer solution was then crosslinked using glutaraldehyde to form the desired hydrogel. The developed silver nanoparticle impregnated chitosan hydrogel was characterized using ultra-violet (UV) visible spectrophotometry, Fourier Transform-infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) followed by the determination of porosity, and swelling properties. The release of AgNPs from hydrogel was determined by UV-vis spectroscopy followed by antimicrobial and antioxidant assays. The wound healing efficacy of the synthesized hydrogel was evaluated in diabetic rabbits. The results demonstrated a higher porosity, higher degree of swelling and higher water vapor transition rate (WVTR) for silver nanoparticle impregnated hydrogel compared to bare chitosan-PEG hydrogel as well as improved antimicrobial and antioxidant properties in-vitro and enhanced wound healing capability in-vivo in diabetic rabbits. The hydrogel showed a slow and sustained release of AgNPs over a period of at least seven days manifesting the slow biodegradation of developed hydrogels. The improved antimicrobial, antioxidant and wound healing results indicate that the silver nanoparticle impregnated chitosan-PEG hydrogel can be a promising material for wound healing dressing for chronic diabetic wounds.
An important application of silver nanoparticles (Ag NPs) is their use as an antimicrobial and wound dressing material. The aim of this study is to investigate the morphological dependence on the ...antimicrobial activity and cellular response of Ag NPs.
Ag NPs of various shapes were synthesized in an aqueous solution using a simple method. The morphology of the synthesized Ag NPs was observed via TEM imaging. The antimicrobial activity of the Ag NPs with different morphologies was evaluated against various microorganisms (
). The antimicrobial activity of the Ag NPs was also examined according to the concentration in terms of the growth rate of
.
The TEM images indicated that the Ag NPs with different morphologies (sphere, disk and triangular plate) had been successfully synthesized. The antimicrobial activity obtained from the inhibition zone was in the order of spherical Ag NPs > disk Ag NPs > triangular plate Ag NPs. In contrast, fibroblast cells grew well in all types of Ag NPs when the cell viability was evaluated via an MTT assay. An inductively coupled plasma mass assay showed that the difference in the antimicrobial activities of the Ag NPs was closely associated with the difference in the release rate of the Ag ions due to the difference in the surface area of the Ag NPs.
The morphological dependence of the antimicrobial activity of the Ag NPs can be explained by the difference in the Ag ion release depending on the shape. Therefore, it will be possible to control the antimicrobial activity by controlling the shape and size of the Ag NPs.
Silver nanoparticles (AgNPs) have garnered significant interest due to their distinctive properties and potential applications. Traditional fabrication methods for nanoparticles often involve ...high-energy physical conditions and the use of toxic solvents. Various green synthesis approaches have been developed to circumvent these issues and produce environmentally benign nanoparticles. Our study focuses on the green synthesis of AgNPs using L-ascorbic acid and explores the modification of their properties to enhance antibacterial and anticancer effects. This is achieved by coating the nanoparticles with Zinc oxide (ZnO) and Silica oxide (SiO
), which alters their optical properties in the visible spectrum. The synthesized formulations-AgNPs, zinc oxide-silver nanoparticles (Ag@ZnO), and silica oxide-silver nanoparticles (Ag@SiO
) core/shell nanoparticles-were characterized using a suite of physicochemical techniques, including Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), Zeta potential measurement, UV-Vis spectroscopy, Refractive Index Measurements, and Optical Anisotropy Assessment. TEM imaging revealed particle sizes of 11 nm for AgNPs, 8 nm for Ag@ZnO, and 400 nm for Ag@SiO
. The Zeta potential values for Ag@ZnO and Ag@SiO
were measured at -17.0 ± 5 mV and -65.0 ± 8 mV, respectively. UV-Vis absorption spectra were recorded for all formulations in the 320 nm to 600 nm wavelength range. The refractive index of AgNPs at 404.7 nm was 1.34572, with slight shifts observed for Ag@ZnO and Ag@SiO
to 1.34326 and 1.37378, respectively. The cytotoxicity of the nanocomposites against breast cancer cell lines (MCF-7) was assessed using the MTT assay. The results indicated that AgNPs and Ag@ZnO exhibited potent therapeutic effects, with IC50 values of 494.00 µg/mL and 430.00 µg/mL, respectively, compared to 4247.20 µg/mL for Ag@SiO2. Additionally, the antibacterial efficacy of AgNPs was significantly enhanced under visible light irradiation. Ag@ZnO demonstrated substantial antibacterial activity both with and without light exposure, while the Ag@SiO2 nanocomposites significantly reduced the inherent antibacterial activity of silver. Conversely, the Ag@ZnO nanocomposites displayed pronounced antibacterial and anticancer activities. The findings suggest that silver-based nanocomposites, particularly Ag@ZnO, could be practical tools in water treatment and the pharmaceutical industry due to their enhanced therapeutic properties.
Today the synthesis of silver nanoparticles is very common due to their numerous applications in various fields. Silver nanoparticles have unique properties such as: optical and catalytic properties, ...which, depend on the size and shape of the produced nanoparticles. So, today the production of silver nanoparticles with different shapes which have various uses in different fields such as medicine, are noted by many researchers. This article, is an attempt to present an overview of the shape-controlled synthesis of silver nanoparticles using various methods.
The unique silver properties, especially in the form of nanoparticles (NPs), allow to utilize them in numerous applications. For instance, Ag NPs can be utilized for the production of electronic and ...solar energy harvesting devices, in advanced analytical techniques (NALDI, SERS), catalysis and photocatalysis. Moreover, the Ag NPs can be useful in medicine for bioimaging, biosensing as well as in antibacterial and anticancer therapies. The Ag NPs utilization requires comprehensive knowledge about their features regarding the synthesis approaches as well as exploitation conditions. Unfortunately, a large number of scientific articles provide only restricted information according to the objects under investigation. Additionally, the results could be affected by artifacts introduced with exploited equipment, the utilized technique or sample preparation stages. However, it is rather difficult to get information about problems, which may occur during the studies. Thus, the review provides information about novel trends in the Ag NPs synthesis, among which the physical, chemical, and biological approaches can be found. Basic information about approaches for the control of critical parameters of NPs, i.e. size and shape, was also revealed. It was shown, that the reducing agent, stabilizer, the synthesis environment, including trace ions, have a direct impact on the Ag NPs properties. Further, the capabilities of modern analytical techniques for Ag NPs and nanocomposites investigations were shown, among other microscopic (optical, TEM, SEM, STEM, AFM), spectroscopic (UV-Vis, IR, Raman, NMR, electron spectroscopy, XRD), spectrometric (MALDI-TOF MS, SIMS, ICP-MS), and separation (CE, FFF, gel electrophoresis) techniques were described. The limitations and possible artifacts of the techniques were mentioned. A large number of presented techniques is a distinguishing feature, which makes the review different from others. Finally, the physicochemical and biological properties of Ag NPs were demonstrated. It was shown, that Ag NPs features are dependent on their basic parameters, such as size, shape, chemical composition, etc. At the end of the review, the modern theories of the Ag NPs toxic mechanism were shown in a way that has never been presented before. The review should be helpful for scientists in their own studies, as it can help to prepare experiments more carefully.
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•Size, shape and chemical composition of AgNPs can be controlled during synthesis.•Artifacts and limitations of the utilized technique can lead to results misinterpretations.•Properties of AgNPs are strictly dependent on the synthesis route.•AgNPs cytotoxicity is a complex process, which related not only to Ag ions release.
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•Graphene-TiO2 coatings were prepared by sol–gel dip-coating method.•AgNPs were photocatalytically grown on graphene - TiO2 nanocomposites.•Differences in AgNPs growth are affected by ...reduced or oxidized form of graphene.•The mechanism of AgNPs growth on TiO2-GO and TiO2-RGO was proposed.
Graphene oxide or reduced graphene oxide-TiO2 (TGO or TRGO) nanocomposites were decorated with Ag nanoparticles (AgNPs) using the photoreduction method. The photocatalytic growth of AgNPs on TGO and TRGO nanocomposites was compared, while keeping the other parameters (i.e., thickness, chemical composition, crystalline structure and the percentage of an area of TiO2 covered by GO or RGO flakes) unchanged. The morphology, structure and chemical composition of TGO-Ag or TRGO-Ag nanocomposites were investigated with the use of SEM-EDS, XPS and Raman spectroscopy. AgNPs were found to be distributed on the surface of TiO2 and on GO or RGO flakes. In-depth research undertaken to explain the effect of GO or RGO used in nanocomposites with TiO2 on the growth of AgNPs showed that there were considerable differences in size and distribution of AgNPs grown on TiO2 and on GO/RGO areas covering TiO2. In addition, the number (n) and size (d) of AgNPs on TGO (n = 37AgNPs/µm2; d = 29 ± 3 nm) or TRGO (n = 34AgNPs/µm2; d = 32 ± 3 nm) do not differ significantly. The theoretical calculations of the weight of silver deposited on the same sample showed that the mass of silver was, on average, twice as high on both types of graphene (9.1(TGO) and 11.2(TRGO) pg/µm2) as on TiO2 (4.8(TGO) and 5.7(TRGO) pg/µm2).
Antifungal Effects of Silver Nanoparticles (AgNPs) against Various Plant Pathogenic Fungi Kim, S.W., Kangwon National University, Chuncheon, Republic of Korea; Jung, J.H., Kangwon National University, Chuncheon, Republic of Korea; Lamsal, Kabir, Kangwon National University, Chuncheon, Republic of Korea ...
Mycobiology,
(Mar 2012), 2012-Mar, 2012-03-00, 20120301, 2012-03, Volume:
40, Issue:
1
Journal Article
Peer reviewed
Open access
This research is concerned with the fungicidal properties of nano-size silver colloidal solution used as an agent for antifungal treatment of various plant pathogens. We used WA-CV-WA13B, ...WA-AT-WB13R, and WA-PR-WB13R silver nanoparticles (AgNPs) at concentrations of 10, 25, 50, and 100 ppm. Eighteen different plant pathogenic fungi were treated with these AgNPs on potato dextrose agar (PDA), malt extract agar, and corn meal agar plates. We calculated fungal inhibition in order to evaluate the antifungal efficacy of silver nanoparticles against pathogens. The results indicated that AgNPs possess antifungal properties against these plant pathogens at various levels. Treatment with WA-CV-WB13R AgNPs resulted in maximum inhibition of most fungi. Results also showed that the most significant inhibition of plant pathogenic fungi was observed on PDA and 100 ppm of AgNPs.
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