Journal articles: 'Silver alloyed nanoparticles'

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Sotiriou, Georgios A., Gion Diego Etterlin, Anastasia Spyrogianni, Frank Krumeich, Jean-Christophe Leroux, and Sotiris E. Pratsinis. "Plasmonic biocompatible silver–gold alloyed nanoparticles." Chem. Commun. 50, no. 88 (2014): 13559–62. http://dx.doi.org/10.1039/c4cc05297h.

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Ristig, Simon, Svitlana Chernousova, Wolfgang Meyer-Zaika, and Matthias Epple. "Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles." Beilstein Journal of Nanotechnology 6 (May 27, 2015): 1212–20. http://dx.doi.org/10.3762/bjnano.6.124.

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Alloyed silver–gold nanoparticles were prepared in nine different metal compositions with silver/gold molar ratios of ranging from 90:10 to 10:90. The one-pot synthesis in aqueous medium can easily be modified to gain control over the final particle diameter and the stabilizing agents. The purification of the particles to remove synthesis by-products (which is an important factor for subsequent in vitro experiments) was carried out by multiple ultracentrifugation steps. Characterization by transmission electron microscopy (TEM), differential centrifugal sedimentation (DCS), dynamic light scattering (DLS), UV–vis spectroscopy and atomic absorption spectroscopy (AAS) showed spherical, monodisperse, colloidally stable silver–gold nanoparticles of ≈7 nm diameter with measured molar metal compositions very close to the theoretical values. The examination of the nanoparticle cytotoxicity towards HeLa cells and human mesenchymal stem cells (hMSCs) showed that the toxicity is not proportional to the silver content. Nanoparticles with a silver/gold molar composition of 80:20 showed the highest toxicity.

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Fleger, Y., and M. Rosenbluh. "Surface Plasmons and Surface Enhanced Raman Spectra of Aggregated and Alloyed Gold-Silver Nanoparticles." Research Letters in Optics 2009 (2009): 1–5. http://dx.doi.org/10.1155/2009/475941.

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Effects of size, morphology, and composition of gold and silver nanoparticles on surface plasmon resonance (SPR) and surface enhanced Raman spectroscopy (SERS) are studied with the purpose of optimizing SERS substrates. Various gold and silver films made by evaporation and subsequent annealing give different morphologies and compositions of nanoparticles and thus different position of the SPR peak. SERS measurements of 4-mercaptobenzoic acid obtained from these films reveal that the proximity of the SPR peak to the exciting laser wavelength is not the only factor leading to the highest Raman enhancement. Silver nanoparticles evaporated on top of larger gold nanoparticles show higher SERS than gold-silver alloyed nanoparticles, in spite of the fact that the SPR peak of alloyed nanoparticles is narrower and closer to the excitation wavelength. The highest Raman enhancement was obtained for substrates with a two-peak particle size distribution for excitation wavelengths close to the SPR.

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Rajendra, Ranguwar, Parnika Bhatia, Anita Justin, Shilpy Sharma, and Nirmalya Ballav. "Homogeneously-Alloyed Gold–Silver Nanoparticles as per Feeding Moles." Journal of Physical Chemistry C 119, no. 10 (February 26, 2015): 5604–13. http://dx.doi.org/10.1021/jp512528j.

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Ristig, Simon, Diana Kozlova, Wolfgang Meyer-Zaika, and Matthias Epple. "An easy synthesis of autofluorescent alloyed silver–gold nanoparticles." J. Mater. Chem. B 2, no. 45 (September 18, 2014): 7887–95. http://dx.doi.org/10.1039/c4tb01010h.

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Clément, Marie, Ibrahim Abdellah, Cyril Martini, Frédéric Fossard, Diana Dragoe, Hynd Remita, Vincent Huc, and Isabelle Lampre. "Gold(i)–silver(i)-calix[8]arene complexes, precursors of bimetallic alloyed Au–Ag nanoparticles." Nanoscale Advances 2, no. 7 (2020): 2768–73. http://dx.doi.org/10.1039/d0na00111b.

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Grasmik, Viktoria, Marina Breisch, Kateryna Loza, Marc Heggen, Manfred Köller, Christina Sengstock, and Matthias Epple. "Synthesis and biological characterization of alloyed silver–platinum nanoparticles: from compact core–shell nanoparticles to hollow nanoalloys." RSC Advances 8, no. 67 (2018): 38582–90. http://dx.doi.org/10.1039/c8ra06461j.

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Liu, Xiang, Jaime Ruiz, and Didier Astruc. "Prevention of aerobic oxidation of copper nanoparticles by anti-galvanic alloying: gold versus silver." Chemical Communications 53, no. 81 (2017): 11134–37. http://dx.doi.org/10.1039/c7cc05129h.

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Prymak, Oleg, Jurij Jakobi, Christoph Rehbock, Matthias Epple, and Stephan Barcikowski. "Crystallographic characterization of laser-generated, polymer-stabilized 4 nm silver-gold alloyed nanoparticles." Materials Chemistry and Physics 207 (March 2018): 442–50. http://dx.doi.org/10.1016/j.matchemphys.2017.12.080.

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Grasmik, Viktoria, Christian Rurainsky, Kateryna Loza, Mathies V. Evers, Oleg Prymak, Marc Heggen, Kristina Tschulik, and Matthias Epple. "Deciphering the Surface Composition and the Internal Structure of Alloyed Silver-Gold Nanoparticles." Chemistry - A European Journal 24, no. 36 (June 19, 2018): 9051–60. http://dx.doi.org/10.1002/chem.201800579.

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Ray, Priyanka, Marie Clément, Cyril Martini, Ibrahim Abdellah, Patricia Beaunier, José-Luis Rodriguez-Lopez, Vincent Huc, Hynd Remita, and Isabelle Lampre. "Stabilisation of small mono- and bimetallic gold–silver nanoparticles using calix[8]arene derivatives." New Journal of Chemistry 42, no. 17 (2018): 14128–37. http://dx.doi.org/10.1039/c8nj02451k.

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Temgire, M. K., Jayesh Bellare, and S. S. Joshi. "Gamma Radiolytic Formation of Alloyed Ag-Pt Nanocolloids." Advances in Physical Chemistry 2011 (April 5, 2011): 1–9. http://dx.doi.org/10.1155/2011/249097.

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Colloidal dispersions of Ag-Pt composite nanoparticles were prepared by gamma radiolysis technique in the presence of nonionic surfactant Brij'97. Simultaneous as well as sequential reduction methods were employed in order to study the structural formation of Ag-Pt bimetallic clusters. Similar shape and trend was observed in optical spectra for both methods. Radiolysis yielded nearly spherical Ag-Pt bimetallic clusters by use of AgNO3 instead of AgClO4. The disappearance of the silver resonance and the simultaneous growth of the 260 nm resonance are independent of cluster structure and degree of alloying. To understand formation of Ag-Pt aggregate, the optical studies were also done as a function of amount of dose absorbed, concentration of surfactant, that is, Brij'97. The shape of the absorption spectrum did not change with increase in gamma radiation dose. TEM analysis exhibited fine dispersions of Ag-Pt clusters surrounded by a mantle when capped with Brij'97. The particle size obtained was in the range of 5–9 nm. On the basis of optical, XRD, and TEM analysis, alloy formation is discussed.

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Hashjin, H. Zabihi, and R. Poursalehi. "Optical Properties of Pure and Alloyed Silver-Copper Nanoparticles Embedded and Coupled in Dielectric Matrixes." Procedia Materials Science 11 (2015): 717–21. http://dx.doi.org/10.1016/j.mspro.2015.11.050.

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Adekoya, Joseph Adeyemi, Enock Olugbenga Dare, Michael Adediran Mesubi, and Neerish Revaprasadu. "Synthesis and Characterization of Optically Active Fractal Seed Mediated Silver Nickel Bimetallic Nanoparticles." Journal of Materials 2014 (March 11, 2014): 1–9. http://dx.doi.org/10.1155/2014/184216.

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The synthesis of new seed mediated AgNi allied bimetallic nanocomposites was successfully carried out by the successive reduction of the metal ions in diethylene glycol, ethylene glycol, glycerol, and pentaerythritol solutions, with concomitant precipitation of Ag/Ni bimetal sols. The optical measurement revealed the existence of distinct band edge with surface plasmon resonance (SPR) in the region of 400–425 nm and excitonic emission with maximum peak at 382 nm which were reminiscent of cluster-in-cluster surface enriched bimetallic silver-nickel sols. The morphological characterization by transmission electron microscopy, high resolution transmission electron microscopy, and X-ray diffraction analyses complimented by surface scan using X-ray photoelectron spectroscopy strongly supported the formation of intimately alloyed face-centered silver/nickel nanoclusters.

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Jenkins, Samir V., Taylor D. Gohman, Emily K. Miller, and Jingyi Chen. "Synthesis of Hollow Gold–Silver Alloyed Nanoparticles: A “Galvanic Replacement” Experiment for Chemistry and Engineering Students." Journal of Chemical Education 92, no. 6 (March 18, 2015): 1056–60. http://dx.doi.org/10.1021/acs.jchemed.5b00042.

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Prymak, Oleg, Viktoria Grasmik, Kateryna Loza, Marc Heggen, and Matthias Epple. "Temperature-Induced Stress Relaxation in Alloyed Silver–Gold Nanoparticles (7–8 nm) by in Situ X-ray Powder Diffraction." Crystal Growth & Design 20, no. 1 (November 21, 2019): 107–15. http://dx.doi.org/10.1021/acs.cgd.9b00728.

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Garcia, P. R. A. F., K. Loza, S. Daumann, V. Grasmik, K. Pappert, A. Rostek, J. Helmlinger, et al. "Combining Small-Angle X-ray Scattering and X-ray Powder Diffraction to Investigate Size, Shape and Crystallinity of Silver, Gold and Alloyed Silver-Gold Nanoparticles." Brazilian Journal of Physics 49, no. 2 (February 20, 2019): 183–90. http://dx.doi.org/10.1007/s13538-019-00642-z.

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Grasmik, Viktoria, Christian Rurainsky, Kateryna Loza, Mathies V. Evers, Oleg Prymak, Marc Heggen, Kristina Tschulik, and Matthias Epple. "Cover Feature: Deciphering the Surface Composition and the Internal Structure of Alloyed Silver-Gold Nanoparticles (Chem. Eur. J. 36/2018)." Chemistry - A European Journal 24, no. 36 (June 19, 2018): 8920. http://dx.doi.org/10.1002/chem.201801307.

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Korir, Daniel K., Bharat Gwalani, Abel Joseph, Brian Kamras, Ravi K. Arvapally, Mohammad A. Omary, and Sreekar B. Marpu. "Facile Photochemical Syntheses of Conjoined Nanotwin Gold-Silver Particles within a Biologically-Benign Chitosan Polymer." Nanomaterials 9, no. 4 (April 11, 2019): 596. http://dx.doi.org/10.3390/nano9040596.

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A simple photochemical method for making conjoined bi-metallic gold-silver (Au/Ag) nanotwins, a new breed of nanoparticles (NPs), is developed. To the best of our knowledge, the photochemical method resulted in distinct, conjoined, bimetallic nanotwins that are different from any well-established alloyed or core-shell nanostructures in the literature. The conjoined Au-Ag NPs possessed surface plasmon resonance (SPR) properties of both metals. The bimetallic nanostructures possessing distinctive optical properties of both metals were obtained using Au NPs as seeds in the first step, followed by the addition of a silver precursor as feed in the second step during a photochemical irradiation process. In the first step, small, isotropic or large, anisotropic Au NPs are generated by photoinduced reduction within a biocompatible chitosan (CS) polymer. In the second step, a silver precursor (AgNO3) is added as the feed to the AuNPs seed, followed by irradiation of the solution in the ice-bath. The entire photochemical irradiation process resulting in the formation of bimetallic Au-AgNPs did not involve any other reducing agents or stabilizing agents other than the CS polymer stabilizer. The small, conjoined Au-Ag bi-metallic NPs exhibited SPR with peak maxima centering at ~400 nm and ~550 nm, whereas the large conjoined nanoparticles exhibited SPR with peak maxima centering at ~400 nm, 550 nm, and 680 nm, characteristic of both gold and silver surface plasmons in solution. The tunability in the SPR and size of the bimetallic NPs were obtained by varying the reaction time and other reaction parameters, resulting in average sizes between 30 and 100 nm. The SPR, size, distribution, and elemental composition of the bi-metallic NPs were characterized using UV-Vis absorption, electron microscopy, and energy dispersive X-ray spectroscopy (EDS) studies.

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Cosovic, V., N. Talijan, D. Zivkovic, D. Minic, and Z. Zivkovic. "Comparison of properties of silver-metal oxide electrical contact materials." Journal of Mining and Metallurgy, Section B: Metallurgy 48, no. 1 (2012): 131–41. http://dx.doi.org/10.2298/jmmb111101013c.

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Changes in physical properties such as density, porosity, hardness and electrical conductivity of the Ag-SnO2 and Ag-SnO2In2O3 electrical contact materials induced by introduction of metal oxide nanoparticles were investigated. Properties of the obtained silver-metal oxide nanoparticle composites are discussed and presented in comparison to their counterparts with the micro metal oxide particles as well as comparable Ag-SnO2WO3 and Ag-ZnO contact materials. Studied silvermetal oxide composites were produced by powder metallurgy method from very fine pure silver and micro- and nanoparticle metal oxide powders. Very uniform microstructures were obtained for all investigated composites and they exhibited physical properties that are comparable with relevant properties of equivalent commercial silver based electrical contact materials. Both Ag-SnO2 and Ag- SnO2In2O3 composites with metal oxide nanoparticles were found to have lower porosity, higher density and hardness than their respective counterparts which can be attributed to better dispersion hardening i.e. higher degree of dispersion of metal oxide in silver matrix.

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Jurkiewicz, Karolina, Michał Kamiński, Wojciech Glajcar, Natalia Woźnica, Fanon Julienne, Piotr Bartczak, Jarosław Polański, Józef Lelątko, Maciej Zubko, and Andrzej Burian. "Paracrystalline structure of gold, silver, palladium and platinum nanoparticles." Journal of Applied Crystallography 51, no. 2 (March 12, 2018): 411–19. http://dx.doi.org/10.1107/s1600576718001723.

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Metallic nanoparticles are of great importance because of their unique physical, chemical, antimicrobial, diagnostic, therapeutic, biomedical, sensing, biosensing, catalytic and optical properties. Detailed knowledge of the atomic scale structure of these materials is essential for understanding their activities and for exploiting their potential. This paper reports structural studies of silica-supported silver, gold, palladium and platinum nanoparticles using X-ray diffraction and high-resolution transmission electron microscopy. Electron microscopy observation allowed the determination of nanoparticle sizes, which were estimated to be in the range of 45–470 Å, and their distribution. The obtained histograms exhibit a multimodal distribution of the investigated nanoparticle sizes. The X-ray diffraction data were analyzed using the Rietveld method in the form of Williamson–Hall plots, thePDFguifitting procedure and model-based simulation. The Williamson–Hall plots provide evidence for the presence of strain in all investigated samples. ThePDFguifitting results indicate that the investigated nanoparticles consist of atomic clusters with different sizes and degrees of disorder as well as slightly different lattice parameters. The detailed structural characterization performedviamodel-based simulations proves that all samples exhibit a face-centered cubic type structure with paracrystalline distortion. The degree of disorder predicted by the paracrystalline theory is correlated with the sizes of the nanoparticles. The catalytic properties of the investigated noble metals are discussed in relation to their disordered structure.

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Heck, Christian, Yuya Kanehira, Janina Kneipp, and Ilko Bald. "Amorphous Carbon Generation as a Photocatalytic Reaction on DNA-Assembled Gold and Silver Nanostructures." Molecules 24, no. 12 (June 24, 2019): 2324. http://dx.doi.org/10.3390/molecules24122324.

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Background signals from in situ-formed amorphous carbon, despite not being fully understood, are known to be a common issue in few-molecule surface-enhanced Raman scattering (SERS). Here, discrete gold and silver nanoparticle aggregates assembled by DNA origami were used to study the conditions for the formation of amorphous carbon during SERS measurements. Gold and silver dimers were exposed to laser light of varied power densities and wavelengths. Amorphous carbon prevalently formed on silver aggregates and at high power densities. Time-resolved measurements enabled us to follow the formation of amorphous carbon. Silver nanolenses consisting of three differently-sized silver nanoparticles were used to follow the generation of amorphous carbon at the single-nanostructure level. This allowed observation of the many sharp peaks that constitute the broad amorphous carbon signal found in ensemble measurements. In conclusion, we highlight strategies to prevent amorphous carbon formation, especially for DNA-assembled SERS substrates.

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Guo, Jia, Xiaoming Mu, Shihao Song, Yanwei Ren, Kai Wang, and Zunming Lu. "Preparation of Ag0 Nanoparticles by EDM Method as Catalysts for Oxygen Reduction." Metals 11, no. 9 (September 20, 2021): 1491. http://dx.doi.org/10.3390/met11091491.

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At present, platinum-based catalysts are the best cathode catalysts, but due to their high prices, they are difficult to use widely. Under alkaline conditions, silver is a better low-cost substitute. Here, a physical preparation method—electrical discharge machining (EDM)—is used to prepare Ag0 nanoparticles. The method is simple and has a high yield. The diameter of prepared nanoparticles is about 30 nm and the nanoparticle surface is rich in defects. These defects enhance the adsorption of O2. In addition, defects can cause tensile strain on the silver catalyst, causing the d-band center of silver to move upward. The defects and the upward shift of the d-band center jointly improve the adsorption energy and catalytic performance of Ag0. This work provides a new method for the engineering construction of surface defects and the preparation of metal catalysts.

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Wacharanad, Sirorat, and Stephan Thierry Dubas. "Tunable Silver Leaching from Polyelectrolyte Multilayers Thin Films." Advanced Materials Research 701 (May 2013): 145–49. http://dx.doi.org/10.4028/www.scientific.net/amr.701.145.

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Silver nanoparticles were deposited on glass slides and surgical suture as antibacterial agent. The silver nanoparticles were prepared by chemical reduction with sodium borohydride and using a synthetic polyelectrolyte as capping agent. Poly (4-styrenesulfonic acid-co-maleic acid) sodium salt PSSMA was used to stabilize the silver nanoparticles and provide an anionic surface charge which then allowed the layer-by-layer deposition method with poly (dially dimethyl ammonium chloride) PDADMAC. Various concentration of capping agent were used to prepare the silver nanoparticles which were then deposited on glass slide and surgical suture. The layer-by-layer deposition of the nanoparticles was studied using UV-Vis spectroscopy by monitoring the intensity of the characteristic Plasmon band of the nanoparticles at 400nm. The leaching of the silver nanoparticles in buffered solutions of pH 3,7 and 9 was monitored by recording the decrease in absorbance of silver nanoparticles film as a function of time for each pH solutions and each capping concentrations. Finally, suture material coated with silver nanoparticles were tested for their antibacterial activity against Staphylococcus aureus and results showed that all coated sutures had more than 99% bacterial reduction. So these suture material could be applied to use in medical products for promoted wound healing and decreased bacterial colony leading to relieve inflammation of patient.

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Joshi, S. C., Utkarsh Kaushik, Aproova Upadhyaya, and Priyanka Sharma. "GREEN TECHNOLOGY MEDIATED SYNTHESIS OF SILVER NANOPARTICLES FROM MOMORDICA CHARANTIA FRUIT EXTRACT AND ITS BACTERICIDAL ACTIVITY." Asian Journal of Pharmaceutical and Clinical Research 10, no. 3 (March 1, 2017): 196. http://dx.doi.org/10.22159/ajpcr.2017.v10i3.16009.

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ABSTRACTObjective: The synthesis of nanoparticles from biological processes is evolving a new era of research interests in nanotechnology. Silver nanoparticlesare usually synthesized by chemicals and physical method, which are quite toxic and flammable in nature. This study deals with an environmentfriendly biosynthesis process of antibacterial silver nanoparticles using Momordica charantia fruit.Methods: AgNO3 (5 mM) was allowed to react with fruit extract of M. charantia. Biosynthesis of AgNPs was optimized by changing temperature,pH, and solvent. The silver nanoparticles so formed were characterized using ultraviolet-visible (UV-VIS) spectroscopy, Fourier transform infraredspectroscopy (FTIR), dynamic light scattering (DLS), atomic force microscope (AFM), and scanning electron microscopy (SEM).Results: UV-VIS spectra show absorption peak between 420 and 430 nm. The FTIR analysis showed the alcoholic, lactam, and nitro group presentin the plant extract, which were responsible for the reduction in AgNPs. The SEM images showed the size distribution of the nanoparticles and theaverage size was found to be 50-100 nm. By DLS analysis and AFM analysis, average sizes of the silver nanoparticles were of 150 nm. The results ofthese analyses confirmed the formation of silver nanoparticles. Silver nanoparticles were tested against Bacillus cereus and Staphylococcus epidermidisstrains using disc diffusion method and were found to be effective.Conclusion: Silver nanoparticles so synthesized in this study using fruit extract of M. charantia are simple, easy, and effective technique of nanoparticlesproduction.Keywords: Silver nanoparticles, Momordica charantia, Optimization, Antibacterial, Atomic force microscope, Scanning electron microscopy.

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Rubira, Rafael Jesus Gonçalves, Sabrina Alessio Camacho, Cibely Silva Martin, Jorge Ricardo Mejía-Salazar, Faustino Reyes Gómez, Robson Rosa da Silva, Osvaldo Novais de Oliveira Junior, Priscila Alessio, and Carlos José Leopoldo Constantino. "Designing Silver Nanoparticles for Detecting Levodopa (3,4-Dihydroxyphenylalanine, L-Dopa) Using Surface-Enhanced Raman Scattering (SERS)." Sensors 20, no. 1 (December 18, 2019): 15. http://dx.doi.org/10.3390/s20010015.

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Detection of the drug Levodopa (3,4-dihydroxyphenylalanine, L-Dopa) is essential for the medical treatment of several neural disorders, including Parkinson’s disease. In this paper, we employed surface-enhanced Raman scattering (SERS) with three shapes of silver nanoparticles (nanostars, AgNS; nanospheres, AgNP; and nanoplates, AgNPL) to detect L-Dopa in the nanoparticle dispersions. The sensitivity of the L-Dopa SERS signal depended on both nanoparticle shape and L-Dopa concentration. The adsorption mechanisms of L-Dopa on the nanoparticles inferred from a detailed analysis of the Raman spectra allowed us to determine the chemical groups involved. For instance, at concentrations below/equivalent to the limit found in human plasma (between 10−7–10−8 mol/L), L-Dopa adsorbs on AgNP through its ring, while at 10−5–10−6 mol/L adsorption is driven by the amino group. At even higher concentrations, above 10−4 mol/L, L-Dopa polymerization predominates. Therefore, our results show that adsorption depends on both the type of Ag nanoparticles (shape and chemical groups surrounding the Ag surface) and the L-Dopa concentration. The overall strategy based on SERS is a step forward to the design of nanostructures to detect analytes of clinical interest with high specificity and at varied concentration ranges.

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Wojnicki, M., I. Mania, M. Marzec, M. Gajewska, and K. Mech. "Influence of Experimental Conditions on Deposition of Silver Nanoparticles Onto Surface of Graphene Oxide / Wpływ Warunków Eksperymentalnych Na Proces Osadzania Nanocząstek Srebra Na Powierzchni Tlenku Grafenu." Archives of Metallurgy and Materials 60, no. 4 (December 1, 2015): 2631–36. http://dx.doi.org/10.1515/amm-2015-0425.

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Present work describes the influence of silver nanoparticles precursor form as well as the impact of graphene oxide initial concentration on deposition of the silver nanoparticles onto graphene oxide. Borane dimethylamine complex (DMAB) was used as the reducing agent. It was observed that application of silver ammonia complexes as the silver nanoparticles precursor as well as alkaline solution effect in higher quantity of deposited AgNPs in comparison to deposition process with the use of silver(I) nitrate in acidic solution.

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Zagoskina, T. Yu, E. Yu Markov, E. A. Chaporgina, Yu O. Popova, T. M. Dolgova, O. V. Gavrilova, T. S. Taikova, et al. "COMPARATIVE ANALYSIS OF EFFECTIVENESS OF SOLID-PHASE METHODS OF IMMUNE DETECTION OF BOTULINIC TOXIN IN BLOOD SERA OF A PATIENT WITH BOTULISM DIAGNOSIS." Journal of microbiology epidemiology immunobiology, no. 5 (October 28, 2017): 64–70. http://dx.doi.org/10.36233/0372-9311-2017-5-64-70.

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Aim. Comparison of effectiveness of solid phase methods of immune detection of botulinic toxin in blood sera of a patient with botulism diagnosis: dot-immune assay using specific anti-botulinic antibodies (AT) labeled with nanoparticles of colloid silver, phosphorescent analysis (PHOSPHAN) using streptavidin label with platinum coproporphyrin (PtCP) and polystyrene nanoparticles, containing chelate complex of europium ions with naphthoyl trifluoroacetone (NA-Eu). Materials and methods. Silver nanoparticle labeled IgG isolated from a commercial diagnostic polyvalent sera against type А, В, С, E, F botulotoxins manufactured by SPA Allergen (Stavropol) with 5000 - 10000 IU activity and biotin conjugated commercial monoclonal antibodies against botulotoxin A, polyclonal mono-specific AB against botulotixin В and E and polyvalent immunoglobulin against botulotoxin А, В, С, E, F. Detection ofbotulotoxin in clinical material was carried out in dot-immunoassay on nitrocellulose membrane by PHOSPHAN method in an experimental test system using 2 detector systems based on streptavidin: PtCP and NA-Eu. Results. Botulotoxin was detected in blood sera of the botulism patient using both of the developed immune detection methods. PHOSPHAN method allowed to identify serotype В botulotoxin, that corresponded with the results obtained in botulotoxin biological neutralization reaction. Sensitivity of PHOSPHAN with NA-Eu luminescent nanoparticle based detection system was higher than with PtCP label. Conclusion. The developed methods (PHOSPHAN and dot-immunoassay) differ by high specificity and sensitivity and may be recommended for express detection of botulinic toxin in clinical material.

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Reyes, Pamela Y., Jesús A. Espinoza, María E. Treviño, Hened Saade, and Raúl G. López. "Synthesis of Silver Nanoparticles by Precipitation in Bicontinuous Microemulsions." Journal of Nanomaterials 2010 (2010): 1–7. http://dx.doi.org/10.1155/2010/948941.

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Silver nanoparticles precipitation was carried out at70∘Cin bicontinuous microemulsions stabilized with a mixture of surfactants sodium bis (2-ethylhexyl) sulfosuccinate/sodium dodecyl sulfate (2/1, w/w) containing an aqueous solution of 0.5 M silver nitrate and toluene as organic phase. Various concentrations of aqueous solution of sodium borohydride (precipitating agent) and their dosing times on microemulsions were studied. Regardless of dosing time, higher and medium concentrations of precipitating agent promoted the formation of worm-like nanostructures, while the lowest concentration allowed to obtain a mixture of isolated silver nanoparticles (mean diameter≈3 nm) and worm-like nanostructures. Experimental yields much higher than those typical in precipitation of silver nanoparticles in reverse microemulsions were obtained. An explanation for formation of worm-like nanostructures based on the development of local zones inside the microemulsions channels with high particle concentrations was proposed.

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Loguercio, Lara Fernandes, Pedro Demingos, Luiza de Mattos Manica, Jordana Borges Griep, Marcos José Leite Santos, and Jacqueline Ferreira. "Simple One-Step Method to Synthesize Polypyrrole-Indigo Carmine-Silver Nanocomposite." Journal of Chemistry 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/5284259.

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A nanocomposite of indigo carmine doped polypyrrole/silver nanoparticles was obtained by a one-step electrochemical process. The nanocomposite was characterized by scanning electron microscopy, infrared spectroscopy, ultraviolet-visible-near infrared spectroscopy, and cyclic voltammetry. The simple one-step process allowed the growth of silver nanoparticles during the polymerization of polypyrrole, resulting in films with electrochromic behavior and improved electroactivity. In addition, polypyrrole chains in the nanocomposite were found to present longer conjugation length than pristine polypyrrole films.

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Antsiferova, Anna A., Marina Yu Kopaeva, Vyacheslav N. Kochkin, Pavel K. Kashkarov, and Mikhail V. Kovalchuk. "Disturbance in Mammalian Cognition Caused by Accumulation of Silver in Brain." Toxics 9, no. 2 (February 3, 2021): 30. http://dx.doi.org/10.3390/toxics9020030.

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The influence of daily prolonged administration of silver nanoparticles on the cognitive functions of a model mammal was studied. The accumulation of silver in the whole brain and the hippocampus, cerebellum, cortex and residual brain tissue of the mouse was investigated by highly precise and representative neutron activation analysis, and histological studies were conducted. Here, we show that long-term memory impairments were caused by the accumulation of silver nanoparticles in the brain and its subregions, such as the hippocampus, cerebellum and cortex, in a step-like manner by disturbance of hippocampal cell integrity. Three different approaches allowed us to observe this phenomenon and discover the reasons it occurred.

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MAURER, T., N. ABDELLAOUI, A. GWIAZDA, P. M. ADAM, A. VIAL, J. L. BIJEON, D. CHAUMONT, and M. BOUREZZOU. "OPTICAL DETERMINATION AND IDENTIFICATION OF ORGANIC SHELLS AROUND NANOPARTICLES: APPLICATION TO SILVER NANOPARTICLES." Nano 08, no. 02 (April 2013): 1350016. http://dx.doi.org/10.1142/s1793292013500161.

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We present a simple method to prove the presence of an organic shell around silver nanoparticles (NPs). This method is based on the comparison between optical extinction measurements of isolated NPs and Mie calculations predicting the expected wavelength of the Localized Surface Plasmon Resonance of the NPs with and without the presence of an organic layer. This method was applied to silver NPs which seemed to be well protected from oxidation. Further experimental characterization via surface enhanced raman spectroscopy (SERS) measurements allowed to identify this protective shell as ethylene glycol. Combining LSPR and SERS measurements could thus give proof of both presence and identification for other plasmonic NPs surrounded by organic shells.

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Pandoli, Omar, Fatima Ventura Pereira-Meirelles, Eric Monteiro Lobo Lobo Luz, Aline Assumpção, Raquel dos Santos Martins, Tommaso del Rosso, and Khosrow Ghavami. "Synthesis of Silver Nanoparticles with Potential Antifungical Activity for Bamboo Treatment." Key Engineering Materials 668 (October 2015): 86–91. http://dx.doi.org/10.4028/www.scientific.net/kem.668.86.

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To increase the durability of bamboo it is important to find an easy method to fill the micro and meso structure of the biological matrix using a nanostructural material with an anti-fungical activity. A colloidal solution of silver nanoparticle (Ag-NPs) is a dispersion of metal nanoparticle in water with a diameter between 5-100 nm. Even if the biological mechanism is not completly understood yet, Ag-NPs show a satisfactory bactericidal and antifungical activity. We present a simple and rapid production of Ag-NPs made by a sol-gel synthesis in flow mode by means of microreactor tecnology through a chemical reduction of AgNO3 with NaBH4 in presence of two different organic ligands: sodium/potassium tartrate and trisodium citrate. The synthesis of Ag-NPs in continuous flow compared to the batch technique allowed to reduce the time of synthesis, facilitating the reproducibility of the process and consequently obtaining NPs with more uniform physical and chemical characteristics. The microorganisms of the genus Aspergillus were used for the microbiological tests. The effect of different Ag-NPs on microbial growth was observed daily. In particular, it was shown that the response of the fungus is inversely proportional to the size of the nanoparticles, cell growth is disrupt depending on the proportion between silver and organic ligand and microbialstatic effect, especially in relation to sporulation stage was also observed.

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Kitsomboonloha, Rungrot, T. Bera, and Joydeep Dutta. "Direct Synthesis of Anisotropic Metal Particles by Ink Jet Printing Technique." Advanced Materials Research 55-57 (August 2008): 585–88. http://dx.doi.org/10.4028/www.scientific.net/amr.55-57.585.

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Here we report the synthesis of nanoparticles with aspect ratios of up to five by synthesis in small concentrated volumes of reactants using an ink-jet printer. Silver and gold nanoparticles were synthesized rapidly on transparent sheets using a commercial ink jet printer. A commercial inkjet printer was modified by replacing conventional inks with different reactants including silver nitrate, ammonium-complex silver, gold chloride reduced by ascorbic acid. The reaction was allowed to occur directly on the substrate within a short reaction time and confined reaction volume defined by the droplet size on the substrate. The nanoparticles and microrods formed on the substrate depend on pH and ionic concentrations of the solutions. The pH of the solutions is an important factor controlling the aspect ratio of microrods. When the concentration of silver ions in the reactant solution was increased the number of particles deposited on the substrate increased subsequently. Anisotropic particles could be formed uniformly over very large area surfaces (1mm x 20mm). This method can be suitable for rapid synthesis of anisotropic particles for potential application in metal-enhanced fluorescence sensing, antibacterial coating, anti reflection coatings, amongst others.

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Ramírez-Acosta, Carlos M., Javier Cifuentes, Juan C. Cruz, and Luis H. Reyes. "Patchy Core/Shell, Magnetite/Silver Nanoparticles via Green and Facile Synthesis: Routes to Assure Biocompatibility." Nanomaterials 10, no. 9 (September 17, 2020): 1857. http://dx.doi.org/10.3390/nano10091857.

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Nanomedicine is entering a high maturity stage and is ready to reach full translation into the clinical practice. This is because of the ample spectrum of applications enabled by a large arsenal of nanostructured materials. In particular, bimetallic patchy core/shell nanoparticles offer tunable surfaces that allow multifunctional responses. Despite their attractiveness, major challenges regarding the environmental impact and biocompatibility of the obtained materials are yet to be solved. Here, we developed a green synthesis scheme to prepare highly biocompatible patchy core/shell magnetite/silver nanoparticles for biological and biomedical applications. The magnetite core was synthesized by the co-precipitation of ferric chloride and ferrous chloride in the presence of NaOH. This was followed by the patchy silver shell’s growth by a green synthesis approach based on natural honey as a reducing agent. A purification process allowed selecting the target patchy nanoparticles and removing excess toxic reagents from the synthesis very efficiently. The obtained patchy magnetite/silver nanoparticles were characterized by UV-Vis spectrophotometry, dynamic light scattering (DLS), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope equipped with energy-dispersive spectroscopy (SEM + EDS), and transmission electron microscopy (TEM). The morphology, patchiness level, and size of the nanoparticles were determined via SEM and TEM. In addition, the spectrophotometric characterization confirmed the presence of the patchy silver coating on the surface of the magnetite core. The nanoparticles show high biocompatibility, as evidenced by low cytotoxicity, hemolytic effect, and platelet aggregation tendency. Our study also provides details for the conjugation of multiples chemistries on the surface of the patchy bimetallic nanoparticles, which might be useful for emerging applications in nanomedicine, where high biocompatibility is of the utmost importance.

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Fernandes, Ricardo J. C., Carlos A. B. Magalhães, Carlos O. Amorim, Vítor S. Amaral, Bernardo G. Almeida, Elisabete M. S. Castanheira, and Paulo J. G. Coutinho. "Magnetic Nanoparticles of Zinc/Calcium Ferrite Decorated with Silver for Photodegradation of Dyes." Materials 12, no. 21 (October 31, 2019): 3582. http://dx.doi.org/10.3390/ma12213582.

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Magnetic nanoparticles of zinc/calcium ferrite and decorated with silver were prepared by coprecipitation method. The obtained nanoparticles were characterized by UV/Visible absorption, XRD, TEM and SQUID. The mixed zinc/calcium ferrites exhibit an optical band gap of 1.78 eV. HR-TEM imaging showed rectangular nanoplate shapes with sizes of 10 ± 3 nm and aspect ratio mainly between 1 and 1.5. Magnetic measurements indicated a superparamagnetic behavior. XRD diffractograms allowed a size estimation of 4 nm, which was associated with the nanoplate thickness. The silver-decorated zinc/calcium ferrite nanoparticles were successfully employed in the photodegradation of a model dye (Rhodamine B) and industrial textile dyes (CI Reactive Red 195, CI Reactive Blue 250 and CI Reactive Yellow 145). The nanosystems developed exhibited promising results for industrial application in effluent photoremediation using visible light, with the possibility of magnetic recovery.

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Typek, Janusz, Nikos Guskos, Grzegorz Zolnierkiewicz, Zofia Lendzion-Bielun, Anna Pachla, and Urszula Narkiewicz. "Magnetic study of Fe3O4/Ag nanoparticles." European Physical Journal Applied Physics 83, no. 1 (July 2018): 10402. http://dx.doi.org/10.1051/epjap/2018170366.

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Nanocomposites of Fe3O4 nanoparticles (NPs) impregnated with silver NPs display antibacterial properties and may be used in water treatment as disinfection agent. Three samples were synthesized: Fe3O4 NPs obtained by the precipitation method and additionally two samples with added silver NPs with mass ratio of Ag:Fe3O4 equal to 1:100 and 2:100. Magnetic properties of these samples were studied by SQUID magnetometry (in temperature range 2–300 K and magnetic fields up to 70 kG) and magnetic resonance technique at RT. Temperature dependence of dc susceptibility revealed the blocking temperature close to RT in all three samples and allowed to determine the presence of single or multi-mode distribution of NP sizes in a particular sample. Isothermal magnetisation measurements showed that the presence of silver NPs, especially those with smaller sizes, decreases the saturation magnetisation. The shape of ferromagnetic loop registered at T = 2 K was used to discuss the sizes of NP magnetic clusters in our samples. Conclusions obtained from analysis of the ferromagnetic resonance spectra were consistent with the propositions based on the magnetometric studies.

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Pagano, Rosanna, Michela Ottolini, Fabio Marzo, Nicola Lovergine, Simona Bettini, Gabriele Giancane, and Ludovico Valli. "Visible light promoted porphyrin-based metal-organic adduct." Journal of Porphyrins and Phthalocyanines 24, no. 05n07 (May 2020): 758–64. http://dx.doi.org/10.1142/s1088424619501347.

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Supramolecular adducts formed by a commercial porphyrin derivative and silver nanoparticles have been obtained using exclusively light as an external trigger that is able to promote the formation of the plasmonic nanostructures. In particular, a water-soluble porphyrin, i.e. tetrakis(4-carboxyphenyl)porphyrin, has been used. It has been thoroughly characterized by means of UV-vis and fluorescence spectroscopy in order to explain its peculiar behavior when illumined with visible photons. Herein we demonstrate that, by means of light illumination, it is possible to tune the porphyrin aggregation state. Furthermore, when the monomeric form of the organic macrocycle is induced and a controlled amount of AgNO[Formula: see text] is simultaneously dissolved, it is possible to promote the formation of silver nanostructures using visible light. The proposed approach allowed porphyrin derivatives/Ag nanoparticles hybrid nanostructures to be obtained without using a chemical reducing agent: the porphyrin derivative simultaneously acts as reducing agent when irradiated by visible light and as a capping agent for the silver nanostructures. The organic/inorganic adduct was characterized by means of steady-state fluorescence that highlights a strong energetic or electronic communication between the two species. XRD and SEM investigations evidence that silver nanoparticles are formed without using any reducing agent.

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Cepoi, Liliana, Inga Zinicovscaia, Tatiana Chiriac, Liudmila Rudi, Nikita Yushin, and Vera Miscu. "Silver and Gold Ions Recovery from Batch Systems Using Spirulina platensis Biomass." Ecological Chemistry and Engineering S 26, no. 2 (June 1, 2019): 229–40. http://dx.doi.org/10.1515/eces-2019-0029.

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Abstract In order to assess ability of Spirulina platensis to recover silver and gold ions from the environment the bioaccumulation of silver and gold ions and their effect on growth, proteins and carbohydrates content of Spirulina platensis biomass was studied. Silver nitrate (AgNO3) in concentration range 0.01-1 mg/dm3 and tetrachloroaurate Na[AuCl4] in concentration range 18.5-370 mg/dm3 were added as component of the Spirulina platensis cultivation medium. In case of silver two cultivation media were studied: standard and Cl-free. The process of silver and gold uptake was traced using neutron activation analysis. Presence of silver ions in standard cultivation medium reduced biomass productivity by 66 %, while in Cl-free biomass productivity was reduced by 11.8 % only. The reduction of proteins content by 30 % in Cl-free medium and by 19 % in standard medium was also observed. The experiments showed that in case of gold ions loading, the biomass productivity and protein content were reduced only at high Na[AuCl4] concentration in the medium. The behaviour of carbohydrates content change was similar under silver and gold loadings: decrease at low metal concentration followed by increase at high metal concentrations. Scanning electron microscopy allowed observation of spherical metal nanoparticles, which were formed extracellularly during silver and gold bioaccumulation. Spirulina platensis can be used for recovery of precious metals as well as metal nanoparticles production.

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No, Jung-Won, Dong-Hyun Kim, Min-Jae Lee, Duck-Hyun Kim, Tae-Hun Kim, and A.-Young Sung. "Preparation and Characterization of Ophthalmic Lens Materials Containing Titanium Silicon Oxide and Silver Nanoparticles." Journal of Nanoscience and Nanotechnology 15, no. 10 (October 1, 2015): 8016–22. http://dx.doi.org/10.1166/jnn.2015.11240.

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Hydrogel ophthalmic lenses containing fluorine-substituted aniline group, titanium silicon oxide nanoparticles, and silver nanoparticles were copolymerized, and the physical and optical properties of the hydrogel lenses were measured. To produce the hydrophilic ophthalmic lenses, the additives were added to the mixture containing HEMA, NVP, MA, EGDMA, and AIBN. The cast mold method was used for the manufacture of the hydrogel ophthalmic lenses, and the produced lenses were completely soaked in a 0.9% NaCl normal saline solution for 24 hours for hydration. The physical properties of the produced macromolecule showed that the water content was 32.5–37.6%, the refractive index was 1.450–1.464, the UV-B transmittance was 0.5–35.2%, and the contact angle was between 56 and 69°. Also, the addition of aniline, titanium silicon oxide, and silver nanoparticles allowed the ophthalmic lenses to block UV. These results show that the produced macromolecule can be used as hydrophilic lenses for ophthalmologic purposes that can block UV.

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Adegoke, Oluwasesan, Kenshin Takemura, and Enoch Y. Park. "Plasmonic Oleylamine-Capped Gold and Silver Nanoparticle-Assisted Synthesis of Luminescent Alloyed CdZnSeS Quantum Dots." ACS Omega 3, no. 2 (February 2018): 1357–66. http://dx.doi.org/10.1021/acsomega.7b01724.

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Yan, Xueting, Bin He, Lihong Liu, Guangbo Qu, Jianbo Shi, Ligang Hu, and Guibin Jiang. "Antibacterial mechanism of silver nanoparticles in Pseudomonas aeruginosa: proteomics approach." Metallomics 10, no. 4 (2018): 557–64. http://dx.doi.org/10.1039/c7mt00328e.

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Silver nanoparticles (AgNPs) are the nanomaterials most widely used as antimicrobial agents in a range of consumer products, due to the environmental release of either the AgNPs themselves or silver ions.

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Gellini, Cristina, Marina Macchiagodena, and Marco Pagliai. "Adsorption Geometry of Alizarin on Silver Nanoparticles: A Computational and Spectroscopic Study." Nanomaterials 11, no. 4 (March 27, 2021): 860. http://dx.doi.org/10.3390/nano11040860.

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The knowledge of the adsorption geometry of an analyte on a metal substrate employed in surface enhanced Raman scattering (SERS) spectroscopy is important information for the correct interpretation of experimental data. The adsorption geometry of alizarin on silver nanoparticles was studied through ab initio calculations in the framework of density functional theory (DFT) by modeling alizarin taking into account all the different charged species present in solution as a function of pH. The calculations allowed a faithful reproduction of the measured SERS spectra and to elucidate the adsorption geometry of this dye on the silver substrate.

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Vélez, Ederley, Gloria Campillo, Gladis Morales, César Hincapié, Jaime Osorio, and Oscar Arnache. "Silver Nanoparticles Obtained by Aqueous or Ethanolic Aloe vera Extracts: An Assessment of the Antibacterial Activity and Mercury Removal Capability." Journal of Nanomaterials 2018 (2018): 1–7. http://dx.doi.org/10.1155/2018/7215210.

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Silver nanoparticles (AgNPs) were synthesized by chemical reduction of Ag+ ions (from silver nitrate AgNO3), using aqueous or ethanolic Aloe vera extracts as reducing, stabilizing, and size control agent. The nanoparticles’ sizes were between 2 and 7 nm for ethanolic extract and between 3 and 14 nm for aqueous extract, as measured by High-Resolution Transmission Electron Microscope (HRTEM). The antibacterial activity against a mesophilic microorganism, Kocuria varians, a Gram-positive coccus, was measured by counting bacterial colonies in agar plate for both extracts. We found that 4% effective concentration is the lowest concentration that completely inhibited visible growth. Mercury removal was investigated by Atomic Absorption Spectroscopy (AAS) measurements, where it was shown that it is not necessary to use high concentrations of nanoparticles for effective removal of mercury inasmuch as with a 20% V/V concentration of both extracts; the Hg(II) removal percentage was above 95%. These results show that the mercury remaining unremoved from the different essays is below the level allowed by World Health Organization (WHO) and the Environmental Protection Agency (EPA).

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Reynoso-García, Paris Jonathan, Marisol Güizado-Rodríguez, Victor Barba, Gabriel Ramos-Ortiz, and Hugo Martínez-Gutiérrez. "Stabilization of Silver Nanoparticles with a Dithiocarbamate Ligand and Formation of Nanocomposites by Combination with Polythiophene Derivative Nanoparticles." Advances in Condensed Matter Physics 2018 (August 1, 2018): 1–9. http://dx.doi.org/10.1155/2018/4376051.

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Spherical morphology for silver nanoparticles (Ag NPs) stabilized with dithiocarbamate (DTC) by reducing silver nitrate with sodium borohydride was obtained, while the addition of sodium citrate and hydrogen peroxide allowed the formation of silver nanotriangles (Ag NTs). Solutions of bright yellow and blue colors characteristic of both morphologies were observed. UV-vis optical analysis of NPs stabilized with DTC showed a plasmonic absorption band at 393 nm characteristic for spherical morphology, while two bands were observed at 332 nm and 762 nm, and a shoulder around 500 nm for the triangular morphology; with these spectra each morphology was confirmed. In these spectra an absorption band between 250 and 260 nm confirms the presence of DTC ligand. The stability of the NPs was achieved using an 8.69 × 10-3 mM solution of 4-(ethylaminodithiocarbamate) methylpyridine di-n-butyltin (IV) through a transmetallation reaction. Silver nanoparticles (Ag NPs) with spherical morphology of average diameter of 12.7 ± 1.2 nm and triangular morphology with 28.9 ± 0.8 nm for each side of the triangles were analyzed by high resolution scanning electron microscopy (HR-SEM). UV-vis spectra also showed the stability of NPs with DTC for more than three months. A copolymer derived of 3-hexylthiophene with (E)-2-(ethyl(4-((4-nitrophenyl) diazenyl) phenyl) amino) ethyl 2-(thiophen-3-yl) acetate (PA) was tested to get polymer NPs by reprecipitation method using THF/water systems. PA Polymer NPs having average diameter of 9.0 ± 1.7 nm were found. By quick and easy procedure, the formation of nanocomposite (NC) of spherical Ag NPs and PA polymer NPs was reached. This NC could be used as imaging agent, electrochemical biosensor, and photonic and optoelectronic device materials.

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Safonov, V V., S. V. Sapozhnikov, D. A. Morozova, and E. V. Zajcev. "Study of electrically conductive carbon textile materials obtained by electrophoretic deposition of graphene oxide." Industrial laboratory. Diagnostics of materials 85, no. 12 (December 29, 2019): 33–37. http://dx.doi.org/10.26896/1028-6861-2019-85-12-33-37.

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Electrophoretic deposition is currently one of the most relevant technological methods for production of electrically conductive materials. In the work, the method of electrophoretic deposition obtained Electrically conductive materials based on carbon fibers (CF) have been obtained for the first time by electro-phoretic deposition using graphene oxide (GO) and silver nanoparticles. The obtained materials exhibit increased electrical conductivity, surface activity, and enhanced physical and mechanical properties. The purpose of the study is development of the methods for producing electrically conductive carbon textile materials by electrophoretic deposition of graphene oxide using galvanic deposition of silver nanoparticles from an electrolyte. Electrophoretic deposition was performed in 1 cm increments and at a constant voltage of 160 V during 20, 40, and 60 sec. Infrared spectroscopy data showed that GO particles are fixed on carbon textile materials. The carbon textile materials (CF/GO/NP Ag/60) thus obtained formed a new structure with several layers of graphene oxide and silver nanoparticles. The CF deposition increases the surface roughness of the hydrocarbon and thus improving the wettability and adhesion. An analysis of the spectra obtained by X-ray photoelectron spectroscopy for CF showed significant changes in the binding energy and the energy of excited photoelectrons. Compared with the initial hydrocarbons, the obtained carbon materials exhibited an increased content of silver and oxygen, whereas carbon to oxygen ratio decreased. The developed technique allowed us to obtain carbon textile materials with high electrical conductivity being 2.5 as much the original CF. Introduction of the silver nanoparticles contributes to filling of the surface cracks in CF. An increase in the share of reduced graphene oxide can significantly increase the surface roughness, electrical conductivity, surface energy and improve the screening properties of carbon textile materials. The effectiveness of screening in the obtained materials is 24.4 % higher than that in the initial CF which expands the potentiality of their application in novel technical textile products of the future.

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Dimitrijevic, R., O. Cvetkovic, Z. Miodragovic, M. Simic, D. Manojlovic, and V. Jovic. "SEM/EDX and XRD characterization of silver nanocrystalline thin film prepared from organometallic solution precursor." Journal of Mining and Metallurgy, Section B: Metallurgy 49, no. 1 (2013): 91–95. http://dx.doi.org/10.2298/jmmb120111041d.

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The Ag nano-structured thin films prepared on flat glass substrates have been studied. The ball-like silver nanoparticles have been synthesized in large quantity by using a modified method of hydrolytic decomposition of silver complexes with amino types ligands formed in ethanol aqueous solution. SEM analysis revealed that Ag nanoparticles are all sphere shaped with bimodal size (40 and 70 nm) distribution. The results of XRD powder pattern examination show that Ag nanoparticles are pure phase, well crystallized. The unit cell dimensions measured on synthesized Ag nano films show small but frequent contraction in comparison to Ag metal standard.

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Köroğlu, Münevver, Burçak Ebin, Srecko Stopic, Sebahattin Gürmen, and Bernd Friedrich. "One Step Production of Silver-Copper (AgCu) Nanoparticles." Metals 11, no. 9 (September 16, 2021): 1466. http://dx.doi.org/10.3390/met11091466.

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AgCu nanoparticles were prepared through hydrogen-reduction-assisted Ultrasonic Spray Pyrolysis (USP) and the Hydrogen Reduction (HR) method. The changes in the morphology and crystal structure of nanoparticles were studied using different concentrated precursors. The structure and morphology of the mixed crystalline particles were characterized through X-ray diffraction analysis (XRD), scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM) and Energy-dispersive X-ray spectroscopy (EDS). The average particle size decreased from 364 nm to 224 nm by reducing the initial solution concentration from 0.05 M to 0.4 M. These results indicate that the increase in concentration also increases the grain size. Antibacterial properties of nanoparticles against Escherichia coli were investigated. The obtained results indicate that produced particles show antibacterial activity (100%). The AgCu nanoparticles have the usage potential in different areas of the industry.

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Pandey, Prem C., Murli Dhar Mitra, Shubhangi Shukla, and Roger J. Narayan. "Organotrialkoxysilane-Functionalized Noble Metal Monometallic, Bimetallic, and Trimetallic Nanoparticle Mediated Non-Enzymatic Sensing of Glucose by Resonance Rayleigh Scattering." Biosensors 11, no. 4 (April 15, 2021): 122. http://dx.doi.org/10.3390/bios11040122.

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Organotrialkoxysilanes like 3-aminopropyltrimethoxysilane (3-APTMS)-treated noble metal cations were rapidly converted into their respective nanoparticles in the presence of 3-glycidoxypropylytrimethoxysilane (3-GPTMS). The micellar activity of 3-APTMS also allowed us to replace 3-GPTMS with other suitable organic reagents (e.g., formaldehyde); this approach has significant advantages for preparing bimetallic and trimetallic analogs of noble metal nanoparticles that display efficient activity in many practical applications. The formation of monometallic gold, silver, and palladium nanoparticles, bimetallic Ag-Pd, and Au-Pd nanoparticles at various ratios of noble metal cations, and trimetallic Ag-Au-Pd nanoparticles were studied; their biocatalytic activity in non-enzymatic sensing of glucose based on monitoring synchronous fluorescence spectroscopy (SFS) was assessed. Of these nanoparticles, Au-Pd made with an 80:20 Au:Pd ratio displayed excellent catalytic activity for glucose sensing. These nanoparticles could also be homogenized with Nafion to enhance the resonance Rayleigh scattering (RRS) signal. In this study, the structural characterization of noble metal nanoparticles as well as bi- and tri-metallic nanoparticles in addition to their use in non-enzymatic sensing of glucose are reported.

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Huo, Can, Mehdi Khoshnamvand, Chenchen Liu, Houyu Wang, Pengle Liu, and Chun-Gang Yuan. "Roles of silver nanoparticles adsorbed ions and nanoparticles’ size in antimicrobial activity of biosynthesized silver nanoparticles." Materials Research Express 6, no. 12 (December 20, 2019): 1250a6. http://dx.doi.org/10.1088/2053-1591/ab608e.

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Journal articles on the topic 'Silver alloyed nanoparticles'

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