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Search for "silver nanoparticles" in Full Text gives 146 result(s) in Beilstein Journal of Nanotechnology.
Tunable longitudinal modes in extended silver nanoparticle assemblies
Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113
- triggered or directed by solution conditions such as temperature, illumination, pH and metal ion concentration [21]. Amongst the various self-assembled nanostructures, silver nanoparticles (AgNPs) are of great significance due to their sharp plasmon resonance, the antimicrobial function and a distinguished
- AgNPs modified by increasing amounts of the three H-bonding ligands: cysteamine, dithiothreitol (DTT) and cysteine. All spectra show a band at 398–410 nm, corresponding to the expected local plasmon resonance for spherical silver nanoparticles of this size. With the addition of a ditopic ligand, this
- -defined, distinct longitudinal band implies that the silver nanoparticles are forming anisotropic aggregates. For cysteine and DTT, at very high ligand-to-nanoparticle ratios, the transverse and longitudinal collapse into a single very broad resonance, which indicates a loss of structural anisotropy in
Templated green synthesis of plasmonic silver nanoparticles in onion epidermal cells suitable for surface-enhanced Raman and hyper-Raman scattering
Beilstein J. Nanotechnol. 2016, 7, 834–840, doi:10.3762/bjnano.7.75
- affiliation: Philips Biocell, Gydevang 42, 3450 Allerød, Denmark Humboldt Universität zu Berlin, 12489 Berlin, Germany 10.3762/bjnano.7.75 Abstract We report fast and simple green synthesis of plasmonic silver nanoparticles in the epidermal cells of onions after incubation with AgNO3 solution. The biological
- the extracellular matrix provides a biological template for the growth of plasmonic nanostructures. This is indicated by red glowing images of extracellular spaces in dark field microscopy of onion layers a few hours after AgNO3 exposure due to the formation of silver nanoparticles. Silver
- demonstrate a templated green preparation of enhancing plasmonic nanoparticles and suggest a new route to deliver silver nanoparticles as basic building blocks of plasmonic nanosensors to plants by the uptake of solutions of metal salts. Keywords: biotemplates; green preparation; onion; plasmonic
Tight junction between endothelial cells: the interaction between nanoparticles and blood vessels
Beilstein J. Nanotechnol. 2016, 7, 675–684, doi:10.3762/bjnano.7.60
- inhibited (79%) by silver nanoparticles (2–6 nm) [80]. Also, AuNPs have the ability to prevent vascular endothelial growth factor (VEGF)- and interleukin-1 beta (IL-1β)-induced proliferation and migration in bovine retinal pigment epithelial cells (BRPEs) through the suppression of the Src kinase pathway
Fabrication and properties of luminescence polymer composites with erbium/ytterbium oxides and gold nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 630–636, doi:10.3762/bjnano.7.55
- and modeled in [6] for nanocomposites with silver nanoparticles and different distances between ions and silver nanoparticles in the range between 10 and 300 nm. Indeed, as it follows from our results (Figure 7) enhancement of the luminescence output was observed in nanocomposites with AuNPs. This
Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution
Beilstein J. Nanotechnol. 2016, 7, 465–473, doi:10.3762/bjnano.7.40
- Physics “Enrico Fermi”, University of Pisa, Largo Bruno Pontecorvo 3, Pisa, 56127, Italy, Department of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino (FI) 50019, Italy 10.3762/bjnano.7.40 Abstract Silver nanoparticles (AgNPs) have increasingly gained importance
- particular, silver nanoparticles (AgNPs) have increasingly gained importance as promising new antimicrobial agents with application in several biomedical fields, in water and air filtration, as well as in conservation of cultural heritage [11][12][13][14]. Although the mode of action of AgNPs against
- in the presence of LiCl would be less oxidized [32]. In addition, the plasmon bands of the silver nanoparticles obtained by ps ablation in both pure water and LiCl solution appear significantly red-shifted compared to those observed for colloids obtained by ns ablation. This result could also be
Surface coating affects behavior of metallic nanoparticles in a biological environment
Beilstein J. Nanotechnol. 2016, 7, 246–262, doi:10.3762/bjnano.7.23
- currently in use for medical purposes [3], for example silver nanoparticles (AgNPs) and superparamagnetic iron oxide nanoparticles (SPIONs). AgNPs are exploited in medicine for biocidal therapy owing to their antibacterial, antifungal, antiviral, and anti-inflammatory properties. In addition, they attract
- bromide (CTA), poly(vinylpyrrolidone) (PVP), poly(L-lysine) (PLL), bovine serum albumin (BSA), Brij 35 (Brij), Tween 20 (Tween) and D-mannose (MAN). Silver nanoparticles coated with sodium bis(2-ethylhexyl) sulfosuccinate (AOTAgNP), cetyltrimethylammonium bromide (CTAAgNP), poly(vinylpyrrolidone) (PVPAgNP
- redispersed in ultrapure water by sonification. Silver nanoparticles directly conjugated to bovine serum albumin (BSAAgNPs) were prepared as follows: 7.6 mL of 50 mM AgNO3 was added dropwise under stirring to 33 mL of ultrapure water containing dissolved 90 mg of BSA. Then, sodium borohydride (1 mL, 0.397 M
Linear and nonlinear optical properties of hybrid metallic–dielectric plasmonic nanoantennas
Beilstein J. Nanotechnol. 2016, 7, 111–120, doi:10.3762/bjnano.7.13
- from metal-island films and microstructured silver films were shown to be related to the enhanced local near-field [22]. Gold and silver nanoparticles in water were shown to enable optical phase conjugation [23][24] with an order of magnitude enhanced optical Kerr coefficient when exciting the
Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure
Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2
- (AFM) measurements of the resulting samples revealed that a similar surface coverage was achieved with both procedures but with a different distribution of silver nanoparticles. In the GO covered LB film, the AgNC distribution is characterized by densely packed regions alternating with empty surface
- GO. Although fabrication of GO-covered nanoparticles has been explored using several methods such as voltammetric co-reduction [33], formation of composite graphene oxide/PAMAM–silver nanoparticles through self-assembly followed by microwave irradiation [34] and GO drop-casting onto amino
- ] proposed to assemble silver nanoparticles to graphene oxide sheets employing electrostatic interactions and a polymer, as adhesive agent, to impart greater stability against aggregation of AgNPs. Previous investigations are generally focused on spherical nanoparticles and only recently Fan et al. reported
Ultrastructural changes in methicillin-resistant Staphylococcus aureus induced by positively charged silver nanoparticles
Beilstein J. Nanotechnol. 2015, 6, 2396–2405, doi:10.3762/bjnano.6.246
- Abstract Silver nanoparticles offer a possible means of fighting antibacterial resistance. Most of their antibacterial properties are attributed to their silver ions. In the present work, we study the actions of positively charged silver nanoparticles against both methicillin-sensitive Staphylococcus
- aureus and methicillin-resistant Staphylococcus aureus. We use aberration-corrected transmission electron microscopy to examine the bactericidal effects of silver nanoparticles and the ultrastructural changes in bacteria that are induced by silver nanoparticles. The study revealed that our 1 nm average
- size silver nanoparticles induced thinning and permeabilization of the cell wall, destabilization of the peptidoglycan layer, and subsequent leakage of intracellular content, causing bacterial cell lysis. We hypothesize that positively charged silver nanoparticles bind to the negatively charged
Nanotechnology in the real world: Redeveloping the nanomaterial consumer products inventory
Beilstein J. Nanotechnol. 2015, 6, 1769–1780, doi:10.3762/bjnano.6.181
- in Standardization (ANEC), joined efforts to develop an inventory of “consumer products with nano-claims” available to consumers in Europe [10]. A new inventory was generated annually from 2009 to 2012, but the 2011 and 2012 versions focused exclusively on products containing silver nanoparticles
- . Titanium dioxide (TiO2), silicon dioxide, and zinc oxide are the most produced nanomaterials worldwide (on a mass basis) and the global annual production of silver nanoparticles represents only 2% of that of TiO2 [20][21]. However, silver nanoparticles are the most popular advertised nanomaterial in the
- compositions, silver is also the most frequently advertised nanomaterial component, with 207 products or 14.5% [11]. Silver nanoparticles are popular consumer product additives due to their well-documented antimicrobial properties [22]. Figure 3 shows how the availability of these major nanomaterial
In situ SU-8 silver nanocomposites
Beilstein J. Nanotechnol. 2015, 6, 1661–1665, doi:10.3762/bjnano.6.168
- photoresist SU-8 has been developed. AgNO3 dissolved in acetonitrile and mixed with the epoxy-based photoresist SU-8 forms silver nanoparticles primarily during the pre- and post-exposure soft bake steps at 95 °C. A further high-temperature treatment at 300 °C resulted in the formation of densely
- homogeneously distributed silver nanoparticles in the photoresist matrix. No particle growth or agglomeration of nanoparticles is observed at this point. The reported new in situ silver nanocomposite materials can be spin coated as homogeneous thin films and structured by using UV lithography. A resolution of 5
- fabricating homogeneous SU-8-based metal nanocomposite thin films with in situ generated silver nanoparticles. These composite materials can be deposited on wafers by using standard spin coating techniques and subsequently structured with UV lithography. The nanocomposite is prepared by dissolving AgNO3
How decision analysis can further nanoinformatics
Beilstein J. Nanotechnol. 2015, 6, 1594–1600, doi:10.3762/bjnano.6.162
- contribution to the overall hazard score [17]. In a case study by Tervonen et al. [18], an MCDA framework was applied for the classification of five nanomaterials: nC60, multiwalled carbon nanotubes (MWCNTs), CdSe, silver nanoparticles (Ag NPs), and aluminum nanoparticles (Al NPs). The SMAA-Tri MCDA model was
- to prioritize research portfolios at the national level. This PDA was an extension of a VOI approach evaluating multiple research topics for three emerging nanomaterials: multiwalled carbon nanotubes, silver nanoparticles, and titanium dioxide nanoparticles [26]. First, a preliminary screening tool
Formation of substrate-based gold nanocage chains through dealloying with nitric acid
Beilstein J. Nanotechnol. 2015, 6, 1362–1368, doi:10.3762/bjnano.6.140
- of nanocages In our previous reports [23][24][25], we have electro-deposited template silver nanoparticles (AgNPs) on ITO substrates and carried out the galvanic replacement reactions. Figure 1 shows top-view and tilted-view SEM images of unreacted AgNP templates and those exposed to aqueous 0.1 mM
Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles
Beilstein J. Nanotechnol. 2015, 6, 1212–1220, doi:10.3762/bjnano.6.124
- scientific studies due to their distinct physicochemical properties [1][2]. Apart from their catalytic and optical features, in particular, silver and gold nanoparticles have begun to play a major role in biochemistry, biology and medicine [3][4][5]. Silver nanoparticles are known to be highly toxic towards
- bacteria [6][7][8]. As a result, they are often employed as antibacterial agents in biomedicine or in consumer products [9][10][11]. Unfortunately, the therapeutic window for silver nanoparticles is rather narrow as silver nanoparticles are also toxic towards eukaryotic cells [11][12]. In contrast, gold
- ablation was reported [25][26][27]. Alloying of presynthesized silver core/gold shell nanoparticles by refluxing with oleylamine [28] or ultrasonication of separate gold and silver nanoparticles [29] was also described. Here, an aqueous co-reduction of silver nitrate and tetrachloroauric acid with a
Improved optical limiting performance of laser-ablation-generated metal nanoparticles due to silica-microsphere-induced local field enhancement
Beilstein J. Nanotechnol. 2015, 6, 1199–1204, doi:10.3762/bjnano.6.122
- characterized by SEM. The particle size and size distribution of the gold and silver nanoparticles are summarized in Figure 1c,d. This shows that the gold nanoparticle diameter distribution ranges from 5 to 30 nm with a maximum at 15 nm. The effect of clustering of the nanoparticles is observed upon drying of
- gold/silica nanocomposites than for the pure gold nanoparticle dispersion. Figure 3c,d shows the optical limiting response and normalized transmittance curves of silver nanoparticles and silver/silica nanocomposites. By adding the silica microspheres, the optical limiting threshold is lowered from 5.4
- to 3.4 J/cm2. The transmittance curves in Figure 3d also show that the optical limiting property of the silver nanoparticles can be improved by addition of silica microspheres. From these results, it can be demonstrated that the optical limiting threshold can be significantly lowered with the
Tattoo ink nanoparticles in skin tissue and fibroblasts
Beilstein J. Nanotechnol. 2015, 6, 1183–1191, doi:10.3762/bjnano.6.120
- accumulation of micrometre- and nanometre-sized silver particles following subcutaneous injection in rats, and found that silver nanoparticles were distributed throughout the main organs especially kidney, liver, spleen, brain and lungs [31]. By contrast, the micrometre-sized silver particles did not get into
Patterning technique for gold nanoparticles on substrates using a focused electron beam
Beilstein J. Nanotechnol. 2015, 6, 1010–1015, doi:10.3762/bjnano.6.104
- structures with gold and silver nanoparticles using a nanomanipulator. This technique is fascinating, but it may be a time-consuming process for production of relatively large circuits. Nanostructures have also been fabricated using focused ion beam- or focused electron beam-induced deposition [1][7
Influence of gold, silver and gold–silver alloy nanoparticles on germ cell function and embryo development
Beilstein J. Nanotechnol. 2015, 6, 651–664, doi:10.3762/bjnano.6.66
- medical and consumer products. Gold and silver nanoparticles play an important role in the current increase of nanoparticle usage. However, our understanding concerning possible side effects of this increased exposure to particles, which are frequently in the same size regime as medium sized biomolecules
- elucidate how composition, size and surface modification of nanoparticles influence viablility and functionality of reproduction relevant cells derived from various animal models. While in vitro cultured embryos displayed no toxic effects after the microinjection of gold and silver nanoparticles, sperm
- showing a dose-dependent response towards protein (BSA) coated gold–silver alloy and silver nanoparticles leading up to complete arrest of maturation. Recent biodistribution studies confirmed that nanoparticles gain access to the ovaries and also penetrate the blood–testis and placental barrier. Thus, the
Hollow plasmonic antennas for broadband SERS spectroscopy
Beilstein J. Nanotechnol. 2015, 6, 492–498, doi:10.3762/bjnano.6.50
- is still higher than that derived from conventional broad-range plasmonic enhancers, such as silver nanoparticles [28]. Moreover, it has been verified that a fine tuning of the optical properties of antennas can be achieved by controlling their geometrical parameters such as height and diameter, in
Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires
Beilstein J. Nanotechnol. 2015, 6, 480–491, doi:10.3762/bjnano.6.49
- spectrum. A shift in the main Raman peak locations is accompanied by the appearance of new spectral features at lower wavenumbers (below 2000 cm−1), as shown in Figure 6 for the case of silver nanoparticles. This occurs also in the case of gold nanoparticles for different excitation wavelengths ranging
- stability observed after mixing with silver nanoparticles [60]. Phenyl-capped polyynes show similar aggregation when mixed with metal nanoparticles. The changes occurring in the vibrational properties of wires upon interaction with metal nanoparticles (i.e., observed comparing Raman with SERS) suggest a
Green preparation and spectroscopic characterization of plasmonic silver nanoparticles using fruits as reducing agents
Beilstein J. Nanotechnol. 2015, 6, 293–299, doi:10.3762/bjnano.6.27
- capability to reduce silver and gold salts and to create silver and gold nanoparticles. We report the preparation of silver nanoparticles with sizes between 10 and 300 nm from silver nitrate using fruit extract collected from pineapples and oranges as reducing agents. The evolvement of a characteristic
- surface plasmon extinction spectrum in the range of 420 nm to 480 nm indicates the formation of silver nanoparticles after mixing silver nitrate solution and fruit extract. Shifts in plasmon peaks over time indicate the growth of nanoparticles. Electron microscopy shows that the shapes of the
- absorption band in the UV. This confirms the evolution of silver nanoparticles from silver clusters. The presence of various silver clusters on the surface of the “green” plasmonic silver nanoparticles is also supported by a strong multicolor luminesce signal emitted by the plasmonic particles during 473 nm
Synthesis of boron nitride nanotubes and their applications
Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9
- combined with the properties of other nanomaterials to construct novel sensor devices for humidity, carbon dioxide detection, and clinical diagnostics. A highly sensitive humidity sensor using BNNTs and silver nanoparticles (AgNPs) for the rapid detection of humidity was fabricated [90]. Figure 8 shows the
SERS and DFT study of copper surfaces coated with corrosion inhibitor
Beilstein J. Nanotechnol. 2014, 5, 2489–2497, doi:10.3762/bjnano.5.258
- the SERS enhancement, could to some extent change the ligand adsorption to copper. Hence, a roughening procedure of smooth copper plates was developed to ensure a suitable SERS activation without the aid of silver nanoparticles. The SERS spectra of 1,2,4-triazole adsorbed on nanostructured copper
Interaction of dermatologically relevant nanoparticles with skin cells and skin
Beilstein J. Nanotechnol. 2014, 5, 2363–2373, doi:10.3762/bjnano.5.245
- penetration of silver nanoparticles (AgNP, mean size 70 nm) in porcine ear skin. By tracking the Raman signal of AgNP, the mean penetration depth in intact skin was found to be 4.4 ± 1.5 µm, which is in accordance with other investigations on silica [3], zink oxide [19], or AgNP in this size range or smaller
- ROS were formed compared to AgNP which were produced and stored in an argon atmosphere. The oxygen in the ambient atmosphere is responsible for the formation of Ag+ ions by oxidation of the metallic silver nanoparticles. Silver ions are probably responsible for the induction of oxidative stress. In
- in EPR signal, no ROS could be detected after particle application alone. A lack of particle penetration with rather superficial radical production in response to UVB exposure could be an explanation. Similarly, no free radical production was detected in skin treated with silver nanoparticles (Figure
Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity
Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237
- calculated that CARS amplification of benzene molecules close to silver particles, averaged over all scattering angles, could be as large as 1021 [50]. Then, in 1994, Liang et al. experimentally demonstrated an enhancement of the CARS signature of benzene in the bulk phase, by adding colloidal silver
- nanoparticles directly into the liquid [79]. Although the phase matching condition was not fulfilled, the average particle spacing had been adjusted such as to be smaller than the coherence length, while the pump wavelength was matching the localized surface plasmon resonance of the silver NPs. In this first
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