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• The chitosan-AgNPs and -CuNPs coatings were obtained by EPD on Ti alloy. • Cytotoxicity and biological protection against two bacteria forms were studied. • The release rate of copper ions into the medium is pH-sensitive. • Chitosan-AgNPs or -CuNPs coatings on TiO 2 demonstrate antibacterial properties. • Chitosan-AgNPs coatings are not cytotoxic against osteoblast cells. Despite numerous studies, the antibacterial efficiency and cytotoxicity of chitosan-based coatings with nanometals need further studies. The purpose of this research was to determine the biological properties of chitosan coatings implemented with either silver nanoparticles (AgNPs) or copper nanoparticles (CuNPs), that were electrophoretically deposited on electrochemically oxidized Ti13Zr13Nb alloy. The SEM tests were used to examine the surface uniformity. The biological tests against human osteoblast cells hFOB 1.19 and antibacterial activity against Staphylococcus aureus and Escherichia coli bacteria were performed. The release of Cu2+ from coating dependent on the pH of medium. The highest was at pH 3.0 and it achieved 47.73 mg/ml. No cytotoxic effects of the chitosan-AgNPs coatings were observed in direct and indirect contact studies, as there was 20 % inhibition of cell growth but no LDH release which indicate the cell breakdown. Antibacterial properties were proven for all modifications, but this effect was stronger for coatings with implemented AgNPs (log degree of bacteria number reduction >3.75 for E. coli and S. aureus). [ABSTRACT FROM AUTHOR]

[Display omitted] • A new system containing graphene oxide, AgNO 3 and waterborne epoxy resin. • A novel epoxy-based coating containing reduced graphene oxide and silver nanoparticle. • UV irradiation led to three reactions simultaneously. • Solved the aggregation of reduced graphene oxide and silver nanoparticles in coating. • Provided a new idea for adding nanoparticles to composite materials. Ultraviolet (UV)-curable waterborne epoxy acrylic resin (EB) containing silver nitrate and graphene oxide (GO) was prepared. A new waterborne epoxy acrylate-based coating (rGO/AgNP/CEB) containing reduced graphene oxide (rGO) and silver nanoparticles (AgNPs) was obtained by the in situ crosslinking of EB and the reduction of GO and silver ion (Ag+) via UV curing. The experimental results showed that UV irradiation combined with glucose effectively reduced GO and Ag+ to rGO and AgNP. Moreover, AgNPs with a diameter of approximately 60 nm were uniformly distributed in the coating. This material can be used for the antifouling of the inner wall of fishponds in mariculture. [ABSTRACT FROM AUTHOR]

• Ag NPs and ZnO Nrds were synthesized separately by polyol and hydrothermal method, respectively. • SERS active substrate composed of Ag NPs is prepared by spin coating and ZnO Nrds was chosen as the probe molecule. • An amplification of the SERS intensity by an order more than 2 times was observed. We reported a simple method to fabricate SERS active substrate composed of Ag NPs where ZnO Nrds was chosen as the probe molecule. Ag NPs and ZnO Nrds were synthesized separately by polyol and hydrothermal method, respectively. Subsequently, we have deposited a roughened surface made of Ag NPs on glass by spin coating. Morphology, phase composition and optical properties of Ag NPs and ZnO Nrds are characterized by Transition Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), X-Ray Diffraction XRD, Raman and Uv–vis Spectroscopy. An amplification of the SERS intensity by an order more than 4.5 times was observed. The responses demonstrated the capability of Ag NPs SERS substrate to be used for detection of heavy metal oxide compounds. Due to the formation of interfacial electric field between Ag NPs and ZnO Nrds, the mechanism of SERS enhancement was discussed. [ABSTRACT FROM AUTHOR]

• Graphene and silver nanoparticles (AgNPs@GO) composite is prepared as lithium anode. • The AgNPs@GO structure offers the Ag active sites to induce the lithium deposition. • The hollow and multi-layer AgNPs@GO exhibits space-confined feature of Li storage. • AgNPs@GO reveals low nucleation overpotential and stabilized Li storage performance. A flower-like oxidized graphene and metal silver nanoparticles composite (AgNPs@GO) was prepared by a spray-drying and annealing process. The AgNPs@GO exhibits three-dimensional (3D) multi-layer heterojunction structure and high surface area, which can reduce the overpotential of lithium deposition, decrease lithium dendrites, and stabilize lithium storage. Especially, an excellent electrochemical performance is obtained due to the space-confined feature of AgNPs@GO structure. At 0.25 mA cm−2 for 0.5 mAh cm−2, the AgNPs@GO-300 reveals a hysteresis voltage of only 32.3 mV at the 10th cycle and a stable coulombic efficiency of 97.1% after nearly 1000 h cycles, indicating promising prospects as lithium metal anode. [ABSTRACT FROM AUTHOR]

The pre-synthesized nano-CIS loaded in PVA was studied for EMI application in X-band. [Display omitted] • The first report on Study of CIS for EMI shielding. • Rapid, one-pot synthesis of copper indium sulphide nano-particles. • Effect of experimental parameter on particle size by XRD. • The method yields surface capped nano-particles. • The CIS/PVA films for potential X-band EMI shielding application. EMI Shielding behaviour of copper indium sulphide (CIS) nanoparticles synthesized by single-step method is presented. 1-Octadecene and oleic acid both play important role in the synthesis, however, presence of oleylamine leads to formation of phase pure CIS as confirmed by XRD. It is observed that incorporation of silver nanoparticles in 1:1 amount with respect to CIS, dramatically enhanced the shielding efficiency from about −3 dB to about −13.5 dB (average) of the CIS/PVA (0.5:1 w/w) composite in X-band. This is possibly the first study of CIS for EMI application. [ABSTRACT FROM AUTHOR]

Highlights • Ag NPs were prepared by the reaction of silver nitrate with alkali hydrolyzed pectin at microwave irradiation. • Small size spherical Ag NPs were produced with average sizes of 2.9 nm and 11.9 nm depending on microwave time. • Obtained Ag NPs colloidal solution were well stable with Zeta potential of near −40 mV. • MICs of Ag NPs against both E. coli and S. aureus were equally at 80–160 µg/ml. Abstract In this work, monodispersed silver nanoparticles (Ag NPs) were prepared by the reaction of silver nitrate with alkali hydrolyzed pectin at microwave irradiation. Two types of Ag NPs were obtained under the following conditions: 400 W of microwave power, 1 g/l NaOH, 2 g/l pectin, 10 mmol/l AgNO 3 , and irradiation time for 1 and 2 min, respectively. The zeta potential values of Ag NPs colloidal solutions were −39.6 and −38.7 mV, indicating that these nanoparticles were stable. Transmission electron microscopy (TEM) analysis revealed these spherical Ag NPs with an average size 2.90 and 11.94 nm, respectively. Ag NPs exhibited potent antibacterial and antifungal activities to against Escherichia coli , Staphylococcus aureus , and Aspergillus japonicus , and the minimum bactericidal concentrations (MIC) to against E. coli and S. aureus were equally at 80–160 µg/ml. In a word, this is a green, efficient, and cost-effective method for Ag NPs synthesis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • AgNs have been synthesized by a green method to improve charge transport in an OSC. • PFN:AgNs mix was used as electron transport layer. • PCE increases due to the use of AgNs. Abstract Low power conversion efficiency represents the main drawback of organic solar cells (OSC) compared to inorganic devices. Therefore, a novel bulk electron transport layer of silver nanostructures (AgNs) inside poly[(9,9-bis(3′-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] is proposed to be used in OSC. Different concentrations (i.e. 5 and 10% v/v) of AgNs synthesized with a natural extract of Agave tequilana Weber var. Azul as reducing agent were used to improve the performance of the photovoltaic devices. Due to the presence of AgNs, which promote better charge transport, an improvement from 7.04 to 32.16% of the overall performance of the OSC was observed compared to the reference device without nanostructures. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • AgNPs decorated mesoporous Si as a novel ascorbic acid (AA) amperometric sensor. • Remarkable sensitivity 1.279 μA µM−1 cm−2, low LOD 0.83 μM and rapid response time <5 s. • The electrochemical oxidation of AA proceeds via diffusion-controlled kinetics. • Electrode accuracy was verified using a real sample of vitamin C tablet. Abstract Novel silver nanoparticles decorated porous silicon (AgNPs-PSi) was fabricated via stain etching of Si, followed by simple immersion plating of Ag and applied successfully for enhanced electro-oxidation and quantification of ascorbic acid (AA). The newly developed nanocomposite consists of mesoporous Si (<20 nm) decorated by crystalline 15–50 nm AgNPs. Remarkable sensing performance was achieved with high sensitivity (1.279 μA μM cm−2), fast response time (<5 s), wide linear range (20–600 μM: R2 = 0.9933), low limit of detection (0.83 μM at S/N = 3) and excellent anti-interference and repeatability behavior. The current Ag-PSi modified glassy carbon electrode was further applied to a commercially available vitamin C supplement with satisfactory detection result. [ABSTRACT FROM AUTHOR]

Highlights • Silver nanoparticles have improving effect on CO sensing characteristics of Co 3 O 4 nanoparticles. • Activation energy of Co 3 O 4 nanoparticles to CO has decreased, due to addition of Ag nanoparticles. • Electronic interaction in energy levels of Ag-Co 3 O 4 affects the sensitivity of sensor. • Ag-Co 3 O 4 nanocomposite has a wide detection range (5–1500 ppm), useful for various CO detection applications. Abstract Co 3 O 4 nanoparticles (NPs) were prepared via a facile coprecipitation method. The carbon monoxide (CO) sensitivity of the as-prepared material was studied at different temperature (50–200 °C) and at different gas concentration (5–1500 ppm). In order to improve the sensor sensitivity, silver (Ag) NPs were loaded on Co 3 O 4 nanoparticles through solution impregnation technique. The crystalline structure, thickness, morphology and elemental composition of the sensing films were characterized by XRD, FE-SEM and EDX analysis. Our results indicated that Ag NPs addition has increased the sensitivity of the Co 3 O 4 NPs based CO sensor. Improving effect of Ag was discussed through activation energy evaluation and energy band diagram. It was concluded that Ag NPs addition, has facilitated CO sensing by decreasing the activation energy and also through the electronic mechanism in the energy levels of Ag-Co 3 O 4 heterocontact. [ABSTRACT FROM AUTHOR]

A biomimetic surface of protein molecule was synthesized and used as a removable template to fabricate stable and monodispersed silver nanoparticles (Ag NPs). Ag NPs with a diameter of 1.8 ± 0.25 nm were obtained, and exhibited excellent catalytic activity in the reduction of 4-nitrophenol with an average activity parameter of 0.892 L·mg −1 ·s −1 . Moreover, the Ag NPs remained stable even after storage at 4 °C for two months, and the activity could be retained up to 88.3%. Therefore, a feasible, straightforward and effective fabrication of stable and monodispersed Ag NPs was achieved herein. It would facilitate the design of functional surface and its application in nano-biomaterials. [ABSTRACT FROM AUTHOR]

Present study reported a simple and green synthesis of silver nanoparticles (AgNPs) synthesized via rapid bio-reduction method. An aqueous extract of Givotia moluccana ( G. moluccana ) plant was serving as reducing and stabilizing agent. An aqueous extract was found to comprise significantly high amounts of secondary metabolites like phenolics, flavonoids, proteins and reducing sugars etc., which are responsible for reducing and capping agents. The synthesized AgNPs were characterized by UV–Visible spectroscopy, FTIR, XRD, FESEM and HRTEM with SAED pattern. Particle size distribution was measured by dynamic light scattering (DLS). Further, thermal analysis of nanoparticles were studied using TGA. Synthesized AgNPs exhibited antimicrobial activity against both gram positive and gram negative bacteria. [ABSTRACT FROM AUTHOR]

• A sandwich structure nanoparticle film is developed for power electronic packaging. • The Ag transition layer provides further driving force for nanoalloy sintering. • The enhancing strategy enables nanoalloy a high reliability die attach material. Bonding interface quality is crucial for power electronic packaging, while the alloyed Ag nanoparticle sintered joint has lower crack resistance at the interface. In this work, a sandwich structure nanoparticle film consisting of an Ag transition layer, nanoalloy layer, and Ag transition layer was developed for interface-enhanced low-temperature bonding. The optimized sandwich structure increased the shear strength of Ag-based nanoalloy sintered joints, reaching 5.6 times for Ag10Cu and 2.0 times for Ag10Pd, respectively. The low-temperature spreadability of the Ag transition layer provided a micro-nano structure and further driving force for nanoalloy sintering on the substrate. Both experimental and molecular dynamics simulation results revealed that these nanoalloy particles spread easier and realized a higher effective bonding area. This interface-enhancing strategy enables the Ag-based nanoalloy a high-reliability die-attach material with low-temperature bondability. [ABSTRACT FROM AUTHOR]

The formation of printed circuit patterns on non-conductive substrates has many applications in high value sectors such as electronics manufacturing. Current semi-additive and subtractive circuit manufacturing processes use photolithography to pattern substrates coated with a thin or relatively thick metal film. This process is often wasteful and expensive. Using an innovative approach; composite Fe 3 O 4 -Ag nanoparticles were synthesized and attracted to a magnetic field. The nanoparticles catalysed electroless copper deposition. Such a catalyst is new to electroless plating and was deposited selectively on a dielectric substrate using a gradient magnetic field. In this way, subsequent electroless copper plating occurred exclusively where the magnetic field was applied, whilst the remaining surface was free of deposited metal. The advantage of this additive method of manufacture is that less material is needed and less waste is produced. [ABSTRACT FROM AUTHOR]

In this paper, the physio-chemical characteristics of green synthesised PLA/silver nanoparticles (PLA-AgNPs) system was investigated for H 2 O 2 sensing. The precursor, silver nitrate (AgNO 3 ) was reduced to nanosilver (n-Ag) by Piper nigrum leaves extract in dual phase medium containing PLA (Capping agent). X-ray photo electron spectroscopy (XPS) analysis was carried out to evaluate the interaction of PLA with silver nanoparticles. The morphological analysis by Transmission electron microscopy (TEM) obtained images of spherical silver particles with average size of about 10–20 nm. The H 2 O 2 sensing was confirmed from the colour fading of the solution and vanishing of the characteristic surface plasmon resonance (SPR) absorbance peak of PLA-AgNPs on adding H 2 O 2 . The proposed sensor can detect even very low concentrations (5 μM) of hydrogen peroxide and finds applicability in biological and environmental analysis. [ABSTRACT FROM AUTHOR]

A controlled growth of nano/micro rods with defined morphologies are of great interest due to its special and unique properties. Here we report ethylene glycol mediated facile and controlled synthesis of ultra-long (∼100 μm) perfect hexagon shaped microrods of silver molybdate by a cost effective method of hydrothermal. The exact conditions are optimized by varying the effective parameters. The synthesis involves the mixing of different concentration of silver nitrate solution (0.025, 0.075, 0.125 M) with ammonium molybdate in the presence of 10 ml of ethylene glycol and then post hydrothermal treatment at 150 °C for 12 hrs. Only 0.075 M conc. of silver nitrate results perfect hexagons whereas the lower and higher concentrations result the formation of distorted edge shaped and longer microrods of Ag 6 Mo 10 O 33 . The magnetic measurement shows the perfect diamagnetic behavior of these mircorods. [ABSTRACT FROM AUTHOR]

The bromide-mediated polyol method has been widely used to synthesize ultrathin silver nanowires, however, the reason why the addition of bromide ions can reduce the diameter of silver nanowires is unclear. To elucidate this mechanism, we have conducted a series of experiments in which the amount of halide ions is kept constant while the ratio of Cl − to Br − ions is varied, to investigate how the halide ions influence the morphology of AgNWs. Based on these experiments and previous studies, we propose herein that the bromide ions fulfill three roles: (i) facilitating the formation of AgBr cubes as nucleation events, (ii) limiting the lateral growth of AgNWs and (iii) enabling the formation of more stable AgBr complexes. Our current study should be useful for enabling size-controlled synthesis of silver nanowires via the bromide-mediated polyol method. [ABSTRACT FROM AUTHOR]

The biosynthesis of silver nanoparticles (AgNPs) using an aqueous extract of an agroindustrial residue of the tequila industry [i.e. leaves of Agave tequilana Weber var. azul (AT)], and silver nitrate or silver acetate as precursor salts is reported. The presence of AgNPs was confirmed by color change, scanning electron microscopy, ultraviolet visible spectroscopy and X-ray diffraction. AgNPs were tested against clinically important bacteria. The effect of extract concentration and the reaction temperature was investigated. Results revealed that, the concentration of AgNPs increases as temperature and extract concentration increase. AgNPs were found to be mainly spherical shaped and showed antibacterial activity against Staphylococcus aureus , Escherichia coli and Pseudomonas aeruginosa . Results demonstrate the possibility of using a natural extract obtained from an abundant agroindustrial residue for the sustainable synthesis of AgNPs. [ABSTRACT FROM AUTHOR]

The Ag and ZnO nanoparticles are synthesized by a green method using Lawsonia inermis plant extract. The phytochemical constituent (2-hydroxy-1, 4-napthoquionone) found in the leaf extract of Lawsonia inermis plays an important role in the reduction and formation of Ag and ZnO nanoparticles. The biosynthesis of Ag and ZnO NPs was observed by the color change from colorless to dark brown and light brown. The FE SEM, TEM DLS analysis confirmed the average particle size of Ag and ZnO NPs as 100 nm, 20 nm, 28.5 nm and 100 nm, 20 nm, 38.4 nm respectively. Crystalline nature and presence of Ag and ZnO NPs were confirmed by XRD. The FT-IR spectra of the Ag and ZnO authorized the presence of phyto constituents as capping agent. From results of acute oral toxicity studies, it was found that Ag and ZnO NPs at 2000 mg/kg b.w have shown no mortality during the treatment period. The present study revealed the safer use of eco-friendly green synthesized Ag and ZnO NPs in the field of nano-biomedicine. [ABSTRACT FROM AUTHOR]

We have demonstrated a one pot green protocol for the synthesis of highly monodispersed silver nanoparticles using leaves of Salvadora persica plant. When the leaf extract of Salvadora persica plant reacted with silver nitrate (AgNO 3 ) solution it resulted in the synthesis of highly monodispersed silver nanoparticles with an average size of 3 nm. These nanoparticles were then completely characterized by UV–Visible spectroscopy, Transmission Electron Microscopy, Energy Dispersive Analysis of X-Rays, X-ray diffraction analysis and Fourier Transform Infrared analysis. [ABSTRACT FROM AUTHOR]

Both Pr 6 O 11 and Ag/Pr 6 O 11 nanorods are the promising catalysts for the photocatalytic degradation of organic pollutant. Hereby, Pr(OH) 3 nanorods were prepared via the ammonia-diffusion process, then Pr 6 O 11 nanorods were obtained by calcining Pr(OH) 3 nanorods. Ag/Pr 6 O 11 nanorods were prepared by depositing Ag on the Pr 6 O 11 nanorods. Photocatalytic capabilities of both Pr 6 O 11 and Ag/Pr 6 O 11 nanorods were investigated with the degradation of Rhodamine B under Xe-lamp irradiation. The results indicated that while the attached Ag suppressed the recombination of photogenerated electron-hole pairs, the extraordinary surface plasmon resonance effect of Ag nanoparticles would enhance the photocatalytic degradation efficiency of Rhodamine B. [ABSTRACT FROM AUTHOR]

• Ti substrate was decorated with AgNPs by electro-reduction. • CS/EE100 or CS/P4VP coatings were deposited in a single electrophoresis process. • The deposited amount of AgNPs on Ti did not cause cytotoxicity against MG-63 cells. • MG-63 cells showed a higher survival rate in contact with CS/EE100 than CS/P4VP. The objective of the study was the determination of the response, in contact with human osteoblast-like MG-63 cells, of electrophoretically deposited coatings composed of chitosan (CS), Eudragit E 100 (EE100), or poly(4-vinylpyridine) (P4VP) on a silver nanoparticle (AgNPs)-decorated titanium substrate. Before deposition, the substrate was coated with silver by electro-reduction of silver nitrate. The coatings deposition was carried out in suspensions containing 0.1 % (w/w) of one of the biopolymers, EE100 or P4VP, with 0.1 % (w/w) of CS for 10 V and 1 min. Biopolymer coatings were successfully deposited while maintaining high uniformity. The deposited silver did not cause cytotoxicity. The biological study revealed that when compared to CS/P4VP, CS/EE100 coating performed better and showed a decrease in MG-63 cell viability only after three days of testing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Silver nanoparticles (AgNPs) were biosynthesized using Opuntia joconostle fruit. • No infusion was required for the formation of AgNPs with mean diameter of 17.7 nm. • AgNPs detect colorimetrically and selectively Hg2+ ion in aqueous solution. • Functionalization of AgNPs is not required for sensing Hg2+ ion even in tap water. Silver nanoparticles (AgNPs) have been synthesized, for the first time, using the pulp of Opuntia joconostle fruit as reducing reagent of Ag+ ions. The reported method is wholly green, since no temperature or infusion preparation were required. AgNPs with a 428 nm plasmon absorbance, a quasi-spherical morphology, a mean size of 17.7 nm, and an FCC crystal structure were obtained. These biogenic AgNPs, without further chemical functionalization, could sense easily (naked eye) and selectively the presence of Hg2+ ions in aqueous solution and in tap water. [ABSTRACT FROM AUTHOR]

Plasmonic silver nanoparticles of varied shapes and sizes (v-AgNPs) were synthesized via facile one-pot chemical reduction method and investigated their applicability in dye sensitized solar cells (DSSCs). The synthesized v-AgNPs exhibit broadband absorption over entire visible region owing to their unique localized surface plasmon resonance (LSPR). The photon conversion efficiency (PCE) of DSSCs increased ∼50% by incorporating ∼1 wt% of v-AgNPs in ∼4 μm thin reference photoanode. The enhancement is mainly due to increase in light harvesting ability of plasmonic photoanode as a result of local electromagnetic field enhancement and strong near field scattering effect of v-AgNPs. In addition, the reduction in charge transfer resistance value (R 2 ) further confirms the high charge carrier generation in plasmonic DSSCs. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (AgNPs) has gained widespread interest as the alternative method to use natural, non-toxic substances to facilitate the formation of AgNPs. This work reported on the alternative source of reducing and stabilizing agents from tissue extract of weaver ant ( Oecophylla smaragdina ) larvae. The formation of AgNPs in the reaction containing silver nitrate, the tissue extract, and glucose at 60 °C was indicated by the surface plasmon resonance at 428 nm. Transmission electron microscopy images revealed spherical AgNPs with the average diameter of 67.4 nm. The synthesized AgNPs exhibited potent antibacterial activity against both Staphylococcus aureus and Escherichia coli with the minimum bactericidal concentrations equally at 16 μg/mL. [ABSTRACT FROM AUTHOR]

Herein, we designed graphene oxide (GO)-encapsulated Ag nanoparticle (AgNP)-coated silk fibers with GO serving as the protective film through hyperbranched poly(amide-amine) (HBPAA)-directed self-assembly for protecting AgNP coatings from detachment. Robust, hard, and closely fitted protective films were achieved on the fiber surfaces through self-assembled GOs by introducing 2D GO nanosheets. Silk fibers were hierarchically coated with HBPAA-capped AgNPs (HBPAA/AgNPs) and GOs by successively impregnating the fibers in solutions of HBPAA/AgNPs and GOs to design a well-defined hierarchical structure. In such structure, HBPAA served as a “double-sided tape” not only gluing AgNPs to the fiber surfaces but also adhering GOs to the surfaces of HBPAA/AgNPs. The developed coaxial cable-structured coatings could isolate Ag nanocoatings from external stimuli, opening a potential route to improve the function persistence and biosafety of AgNP-coated biotextiles. [ABSTRACT FROM AUTHOR]

The present study has been investigated for the formation of silver nanoparticles (AgNPs) toxicity was reduced by a biological route employing methanolic extract of Gloriosa superba seed (MGsS) extract. AgNPs protected with -CH2- group, –NH2– groups and –CO– groups of colchicines and colchicine derivatives of Gloriosa superba seed extract are not cytotoxic, while, by contrast bare AgNPs have been found to be rather toxic. Capping and efficient stabilization of silver ions by MGsS confirmed by FTIR analysis. TEM analysis also revealed that the edges of the particles were lighter than the centers, confirmed that the bioorganic compounds such as alkaloids (colchicines) in MGsS capped the silver NPs contributing to reduction of Ag + ions to Ag°. Formation of AgNPs was confirmed by UV–visible absorbance peaks at 360 and 440 nm clearly indicated the interaction between AgNPs and biomolecules present in the MGsS. The XRD study confirmed the crystalline face-centered cubic lattice of AgNPs of methanolic extract of Gloriosa superba seed (AgMGsS). The average size of the nanoparticles was determined to be about 35–42 nm. [ABSTRACT FROM AUTHOR]

The present study reports the biological synthesis of silver nanoparticles (AgNPs) using the aqueous extract of fresh basidiocarps of the tree oyster mushroom, Pleurotus ostreatus. The AgNPs solution exhibited an absorption maximum at 440 nm, corresponding to surface plasmon resonance of AgNPs. The field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) analyses revealed that the synthesised AgNPs were spherical in shape and the particle size was less than 40 nm. The energy dispersive x-ray analysis (EDX) spectrum showed peaks for the presence of silver, carbon and oxygen atoms in the range of 2.8–3.2 keV. Fourier transform infra-red spectroscopy (FTIR) results showed the binding properties of bio-constituents responsible for capping and stabilizing the nanoparticles. The synthesised AgNPs significantly (p<0.05) inhibited the growth of all bacterial species tested. The MIC of the tested bacterial spp. were in the range 13–27 µg/mL. The results of this study indicated that the synthesised AgNPs may be developed as an effective agent against bacterial infections. [ABSTRACT FROM AUTHOR]

A facile eco-friendly synthesis of silver nanoparticles (AgNPs) using Verbascum thapsus ( V. thapsus ) flower extract as reducing as well as stabilizing agent is reported. The morphology of the synthesized Ag-NPs was spherical when examined with transmission electron microscopy (TEM). UV spectral analysis showed surface plasmon bands around 412 nm, with increased intensity and peak narrowing as the reaction time increased from 15 to 120 min. FTIR studies revealed the presence of bioactive functional groups which acted as capping and stabilizing agents of the nanoparticles. The AgNPs exhibited excellent catalytic activity towards the photodegradation of nitrobenzene. The percentage degradation studied for 20 and 48 h reaction time, using 120 mg/L and 1200 mg/L nitrobenzene was estimated to be 79.5% and 87.5% respectively. [ABSTRACT FROM AUTHOR]

A unique way to control the size and antibacterial activities of silver nanoparticles (Ag NPs) using three different leaf conditions (fresh, oven-dried and sun-dried) of Alstonia scholaris has been reported in this paper. The extract of the A. scholaris leaf acts both as a reducing and stabilizing agent in the formation of Ag nanoparticles. The characteristic surface plasmon peak (415 nm), X-ray diffraction (XRD) studies and energy dispersive spectroscopy (EDS) confirmed the formation of crystalline green Ag nanoparticles. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that there was a difference in size for the Ag NPs synthesized from different leaf conditions. Antibacterial studies with both Gram-positive and Gram-negative bacteria showed that Ag NPs synthesized from the fresh leaves displayed the best antibacterial activity, which can be attributed to the size effect of the nanoparticles. [ABSTRACT FROM AUTHOR]

In this study, a simple one-step co-deposition process was introduced to fabricate antibacterial surfaces for synthetic materials via UV-inducing dopamine polymerization combined with in situ formation of Ag nanoparticles. The successful formation of a composite coating was demonstrated by scanning electron microscopy. Antibacterial experiments including antibacterial rate test and bacteria adhesion were evaluated in vitro. The results confirmed the excellent antibacterial property of this surface modification process. In conclusion, the approach presented here provides a simple and effective approach to construct antibacterial surfaces for synthetic materials to meet the requirements of daily life and industry application. [ABSTRACT FROM AUTHOR]

AgInZnS/RGO nanocomposites was prepared by a facile hot-injection method and the corresponding photoelectric detection device was further designed for studying the photoresponse property. The as-prepared AgInZnS/RGO nanocomposites was composed of AgInZnS nanoparticles of 7–8 nm and reduced graphene oxide (RGO) nanosheet. Moreover, the AgInZnS/RGO nanocomposites demonstrated slight red-shifted absorption and photoluminescence quenching, which could be attributed to the effective separation of photon-generated carrier of AgInZnS nanoparticles and fast electrical transportation of RGO sheet. Furthermore, the as-prepared AgInZnS/RGO nanocomposites showed relatively strong photoresponse, comparable short rise-time (0.62 s) and decay-time (0.29 s), which makes it as promising applications in photoelectric detection. [ABSTRACT FROM AUTHOR]

Biological entity is gaining significant prominence in green synthesis of silver nanoparticles as a result of their potential applications in nanomedicine and material engineering. Herein, we have reported the green synthesis of Artocarpus altilis silver nanoparticles (BAgNPs) using aqueous leaf extract of Artocarpus altilis . Synthesized colloidal BAgNPs were confirmed spectrophotometrically at 432 nm and the various reaction conditions were optimized. The SEM, TEM and DLS analysis confirmed that the average particle size of BAgNPs was 34 nm, 38 nm, and 162.3 d.nm, respectively. Nature and presence of silver were confirmed by XRD and EDX. Further, FT-IR spectra of the synthesized BAgNPs authorized the presence of phyto constituents as capping agent. The BAgNPs showed moderate antimicrobial and antioxidant activities. The present study revealed the safer use of eco-friendly green synthesized BAgNPs in near future in the field of biomedicine, water treatment or purification, and nanobiotechnology. [ABSTRACT FROM AUTHOR]

In the present work, facile syntheses for titanium dioxide (TiO 2 ), Silver (Ag), and Ag/TiO 2 nanoparticles were applied through sol-gel technique. Structural and morphological characterizations were followed by UV, TEM, and SAED. The cup agar diffusion method was followed to investigate the bactericidal activities against three common bacterial strains being Escherichia coli (Gram-negative), Bacillus subtitles and Staphylococcus aureus (Gram positive). The bactericidal activities were evidenced by the inhibition zones of the bacterial growth around the resultant substrates. The results prove promising bactericidal activity of Ag and Ag/TiO 2 nanophases compared to TiO 2 anatase phase nanoparticles possessing no bactericidal activity. The combined presence of silver nanoparticles along with the anatase phase induced a promising bactericidal activity. [ABSTRACT FROM AUTHOR]

Soy leaf extract mediated bioreduction process has been successfully employed for the decoration of graphene sheets with silver nanoparticles. Silver content on the graphene sheets has been varied by manipulating the silver nitrate concentration in the reaction mixture. Using transmission electron microscopy, it has been found that the silver nanoparticles deposited on the graphene sheets existed in spherical shape with the diameter range of 2–25 nm. The crystalline features of the graphene samples with silver nanoparticles were investigated by means of X-ray diffraction. XRD patterns illustrated the co-existence of graphene and silver phases, in which, the silver nanoparticles found with the cubic crystal structure with a lattice constant of 4.0853 Å. SEM-EDS analysis was utilized to analyze the silver content of the samples. It was shown with an increase in silver nitrate concentration from 1 mM to 5 mM, the silver content in the samples increased from 0.35% to 1.05%. [ABSTRACT FROM AUTHOR]

In this investigation, silver nanoparticles having a size ranging from 5 to 40 nm have been fast-biosynthesized by Tamarix gallica plant extract. The Ag nanoparticles obtained at room temperature by exposing the silver nitrate ions to the plant extract in an aqueous solution were characterized by UV–vis spectroscopy, FT-IR spectroscopy, X-ray diffraction, and scanning and transmission electron microscopy techniques. The biosynthesis process of spherical Ag nanoparticles exhibits a high rate of bioreduction being less than a 5 min reaction. UV–vis spectroscopy shows a surface plasmon resonance band located at 426.7 nm. The FT-IR spectrum of nanoparticles showed the presence of CO functional group that can be associated with the removal of aromatic compounds (benzenes) to form the nanometer solids. The antibacterial activity against Escherichia coli of silver nanoparticles synthesized with Tamarix gallica extract was confirmed. [ABSTRACT FROM AUTHOR]

Nanoparticles composed of silver and silver chloride (Ag@AgCl NPs) are synthesised by a two-step procedure; (1) Synthesis of silver chloride nanoparticles (AgCl NPs) via phyto reduction mixing an aqueous extract from needles of Pinus densiflora (red pine) with an aqueous solution of silver nitrate (AgNO 3 ) in the absence of light; and (2) synthesis of Ag@AgCl NPs via photo reduction exposing AgCl NPs to light from a solar simulator. The optical properties and elemental composition of as-synthesised Ag@AgCl NPs are examined for further applications of the nanoparticles as a plasmonic photocatalyst. [ABSTRACT FROM AUTHOR]

• Capric–Myristic acid (CA-MA) binary mixture is proposed for building applications. • Silver- Graphene nanoplatelets (Ag-GNP) (1% wt) was used as hybrid nanocomposites. • Melting and freezing temperature of CA-MA/Ag-GNP (1 % wt) are 18.7 °C and 15.7 °C. • The thermal conductivity of CA-MA/Ag-GNP (1% wt) was enhanced by 18.52 %. • The prepared CA–MA/Ag-GNP (1% wt) mixture are suitable for building applications. The capric-myristic acid binary eutectic mixture (CA-MA) was prepared as phase change material (PCM) for building applications; later, novel hybrid-nanocomposites of silver–antimony tin oxide (Ag-ATO) and silver-graphane nanoplatelets (Ag-GNP) were added with CA-MA with a weight percentage of 1 and 2 respectively to form a hybrid-nanocomposite PCMs (HNCPCMs). The chemical and thermal characterization of pure CA-MA and HNCPCMs showed that their stability is significant for building applications. The melting temperature (T m) and freezing temperature (T f) of pure CA-MA synthesised are 18.15 °C and 16.00 °C, respectively, with melting latent heat (H m) and freezing latent heat (H f) of 158.75 J/g and 158.07 J/g, respectively. An HNCPCM of CA-MA/Ag-GNP (1 % wt) shows an improved melting thermal conductivity of 18.52 %, with negligible deviation in melting-freezing temperature and latent heat. The proposed CA-MA/Ag-GNP (1 % wt) has significant thermal, chemical, and long-term cycling reliability, making it a promising material for building applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlight • Biosynthesis of Ag nanoparticles in a hydrodynamic cavitation system. • Hydrodynamic cavitation enhanced continuous biosynthesis of AgNPs. • The synthesis process without pH enhanced at room temperature. • ESR applied to detect the mechanism. Abstract Hydrodynamic cavitation (HC) was employed in order to enhance the biological reducibility of biomass to produce silver nanoparticles (AgNPs) readily. UV–Vis spectra analysis, TEM, HRTEM, SAED and XRD were used to characterize the materials. The results confirmed that AgNPs with uniform distribution could be successfully synthesized by hydrodynamic cavitation enhanced biosynthesis using CP (C. Platycladi) leaf extract (0.3 g/L) without pH enhanced at room temperature (30 °C). Finally, the electron spin resonance (ESR) technique was then applied to detect the mechanism of the enhanced biosynthesis of AgNPs in the HC system. It is concluded that the "hot spot" generated resulting from bubble collapsing is the crucial factor to enhance the reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • MgB-NPs nanoparticles were synthesized using chemical wet-precipitation method. • Ag MgB-NPs nanoparticles were fabricated. • Ag MgB-NPs displayed a good cytocompatibility. • The excellent antibacterial activity of Ag MgB-NPs was confirmed. The development of new calcium phosphate nanoparticles with excellent cytocompatibility and antibacterial properties is generating substantial interest in the biomedical field. In this regard, the present study demonstrated the synthesis of magnesium-doped biphasic calcium phosphate nanoparticles containing silver (Ag MgB-NPs) via the employment of the chemical wet-precipitation method. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and ultraviolet–visible spectroscopy (UV–Vis) methods were used to confirm the successful synthesis of Ag MgB-NPs. X-ray photoelectron spectroscopy (XPS) and Raman spectra indicated that Mg2+ was doped at the Ca2+ position. The excellent cytocompatibility of Ag MgB-NPs was confirmed using the cell counting kit-8 (CCK-8) analysis which employed a culture of human bone marrow-derived mesenchymal stem cells (hBMSCs). Additionally, the antibacterial activity of Ag MgB-NPs was evaluated using Gram-negative E. coli and Gram-positive S. aureus micro-organisms. The present study therefore developed novel calcium phosphate nanoparticles that were demonstrated to have the potential for biomedical applications. [ABSTRACT FROM AUTHOR]

In biogenic synthesis of nanoparticles, plant extracts can be implemented as a source for electrons and stabilizers during chemical reduction of metallic ions in order to form nanoparticles. Experimental conditions of this procedure play vital roles in the synthesis rate of the product. Here, a response surface methodology was employed for the optimization of Ag-conjugated nanoparticles biosynthesis mediated by Persian walnut (Juglans regia) green husk extract. The individual and interactive effects of process variables (temperature, time, concentration and pH) on the production rate of the final product were monitored and the best second-order polynomial model with high coefficient of determination ( R 2 ) value was constructed. Later, optimal reaction conditions for the maximum production rate were found at the reaction temperature of 51.27 °C, duration of 71.45 min, pH of 6.82 and concentration of 8%. These data can be employed in large scale production of nanoparticles mediated by walnut green husk extract. [ABSTRACT FROM AUTHOR]

The structural and field emission properties of CuO nanoribbons decorated with Ag nanoparticles by a wet chemical method were investigated. The results demonstrated a remarkable enhancement of field emission performance of CuO nanoribbons decorated with Ag nanoparticles. The effect of Ag amount on the field emission performance was studied in detail, and excellent field emission properties such as a low turn-on electric field of 2.1 V/μm and a high field enhancement factor of 2528 were obtained. [ABSTRACT FROM AUTHOR]

A medicinally important Sida cordifolia leaf extract has been used for biogenic synthesis of silver nanoparticles (AgNPs) in presence of sunlight and demonstrated enhanced biological activities. AgNPs were characterized using UV–vis spectroscopy, Fourier Transform Infrared spectroscopy (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM), Zeta potential and energy dispersive X-ray analysis (EDAX). Interestingly, bio-functionalized AgNPs displayed higher antioxidant activity in terms of reducing power on ferric ion (1.83 AU) and phosphomolybdate (2127 Ascorbic acid Equivalent Antioxidant Activity) and radical scavenging activity against superoxide (IC50 value 46.25 µg/ml) and DPPH radicals (IC50 value 50.12 µg/ml) compared to the standard. AgNPs has also exhibited cytotoxic effect with IC 50 value of 204 and 129 µg/ml against EAC and HT-29 cancer cell lines, respectively which indicates the AgNPs are effective than that of commercially available drug. Thus, enhanced biological activities have been achieved by incorporating AgNPs with biologically active molecules. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were synthesized in low cost skim natural rubber latex by adding silver nitrate as a source of silver ions. Left-over ammonia in latex was believed to form a complex with silver ions before reacting with the reducing agents which were glucose and other organic compounds in latex. Moreover, protein in latex could also control the growth of the particles by acting as a stabilizing agent. Many factors, which include ammonia content, d -glucose content and BSA protein content, were studied to clarify their effects in the synthesis. The emergence of AgNPs was checked with UV–visible spectrometer and electrical conductivity meter. Transmission electron microscope (TEM) was applied to study the particle morphology. The results showed that UV absorbance (ABS) and conductivity of the reacting suspension increased when ammonia content and d -glucose content increased, implying an increasing number or growth of particles. In contrast, ABS and conductivity decreased with increasing BSA content, showing that smaller particles were formed. The TEM images confirmed that the size of AgNPs in the none-added sample was 6–26 nm. The synthesized AgNPs could inhibit the growth of Escherichia coli and Staphylococcus aureus . [ABSTRACT FROM AUTHOR]

Silica core shell silver nanoparticles (Ag@SiO 2 NPs) have been prepared by a one step synthesis in an eco-friendly way. Biological fermented product, i.e. whisky was used as a reducing agent for silver ions and as a catalyst for the formation of silica shell on silver nanoparticles (AgNPs). The structural and morphological studies were done by various analytical techniques to reveal its crystalline nature and core-shell structure. The catalytic activity of Ag@SiO 2 NPs for the reduction of mixture of 4-nitrophenol (4-NP) and rhodamine-B (Rh-B) in presence of NaBH 4 and its reusability are demonstrated. The antibacterial activity of Ag@SiO 2 NPs against Escherichia coli ( E. coli ), Bacillus cereus ( B. cereus ), and Staphylococcus aureus ( S. aureus ) was studied. [ABSTRACT FROM AUTHOR]

Plasmonic metals such as gold, silver and copper are optically attractive photosensitizers owing to its unique optical properties at nano-scaled level, where the unique surface plasmon resonance (SPR) phenomenon becomes operative. These photosensitizers are usually deposited by immersion techniques which impart poor control on density of these photosensitizers dispersed on semiconductors. Herein, we report the deposition of silver NPs on TiO 2 semiconductor by employing pulsed laser deposition (PLD). PLD efficiently deposits Ag NPs on TiO 2 with effective control on NPs distribution on photoanodes which, ultimately, tune the photovoltaic (PV) characteristics of the resultant NPs sensitized solar cells, since the formed NPs sizes and morphology, and their spatial distribution on semiconductor have a significant influence on the PEC performance. [ABSTRACT FROM AUTHOR]

The present study was aimed at the biosynthesis of silver nanoparticles (AgNPs) using aqueous extract of Clerodendron serratum (AECS) leaves and testing their potential in vitro anticancer activity using Ehrlich ascites carcinoma (EAC) cell lines. This medicinal plant was found to be rich in polyphenol glycosides and two compounds-baicalein and quercetin 3-O-β- d -glucoside was isolated from the extract. The biologically synthesized AgNPs were characterized using UV–vis spectrophotometry, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). The antiproliferative ability of the AgNPs was evaluated using cell viability and MTT assays and the results showed that biosynthesized AgNPs possesses significant in vitro antiproliferative activity. [ABSTRACT FROM AUTHOR]

In the present study, silver nanoparticles (Ag NPs) were successfully synthesized by treating silver ions with peach gum polysaccharide (PG) under solar radiation. The Ag NPs were crystallized in the face centered cubic with an average particle size of 23.56±7.87 nm. The possible synthesis mechanisms were elucidated through FTIR. The PG mediated Ag NPs were successfully applied in analytical procedures for the colorimetric sensing of H 2 O 2 . The detection limit is found to be 0.035 µM, which is lower than certain enzymebased biosensors. [ABSTRACT FROM AUTHOR]

This study reports the green synthesis of silver chloride nanoparticles (AgClNPs) and silver nanoparticles (AgNPs) from aqueous corn husk extracts. The effect of changes in the extract volume and the pH on the green synthesis of these nanoparticles is investigated. The formation of AgClNPs and AgNPs was monitored using a UV–vis spectrophotometer. XRD was used to characterize AgClNPs and AgNPs, and it was determined that, by varying the pH, it is possible to control the synthesis of both nanoparticles in a single pure phase. FTIR showed that the phytochemicals from the corn husks are responsible for the reduction and stabilization of the resulting particles. TEM analysis showed the formation of crystals with average sizes of 20 nm, and the SEM-EDS analysis validated the presence of silver. The synthesized nanoparticles had antibacterial activity against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Transparent and conductive silver nanowires (AgNWs)-filled methylcellulose (MC) composite films were fabricated by blending silver nanowires (AgNW) with a methylcellulose solution. AgNW concentration showed significant influence on the optical, electrical and mechanical properties of composite films. The percolation threshold of AgNWs-filled methylcellulose composite films in this study was approximately 0.29 vol%. A three-dimensional (3D) network-like composite film with micron-scale thickness demonstrated the electrical percolation of the two-dimensional (2D) network. Methylcellulose blended with silver nanowires showed enhanced mechanical properties such as tensile strength and Young׳s modulus compared with pure methylcellulose matrix. [ABSTRACT FROM AUTHOR]

• The antimicrobial properties of AgNPs are affected by their size. • The viscosity of the reaction system and size of crystal growth space affect AgNPs size. • Preparing AgNPs by using N -maleoyl chitosan and montmorillonite. • Higher antibacterial ability and lower cytotoxicity. The antimicrobial properties of silver nanoparticles (AgNPs) are significantly affected by their size. In our previous study, we synthesized low-toxicity AgNPs using chitosan derivatives. As chemical reductants and stabilizers were not used in the preparation process, the toxicity of the products was very low. However, the size of the as-obtained nanoparticles was relatively large (100–150 nm). In this study, we used N -maleoyl chitosan and montmorillonite to prepare small-sized green AgNPs and investigated the effect of the reaction system viscosity and crystal growth space on the formation of small-sized nanoparticles. We found that increasing the viscosity of the reaction system or controlling the crystal growth space was conducive to the green preparation of small-sized AgNPs. The prepared AgNPs had higher antibacterial ability and lower cytotoxicity. To the best of our knowledge, this is the first time that AgNPs with such a small size (less than 5 nm) have been prepared using a simple and completely green method. [ABSTRACT FROM AUTHOR]