High-density Silver Nanoparticles Research Articles

Synthesis of dendrimer stabilized high-density silver nanoparticles on reduced graphene oxide for catalytic and antibacterial properties

Study explores depositing silver nanoparticles onto dendrimer-functionalized reduced graphene oxide via a Diels–Alder reaction, analyzing dendrimer branching's impacts on AgNP loading, nitro-reduction, and antibacterial properties.

ANTI-DIABETIC EFFECT OF GREEN SYNTHESISED SILVER NANOPARTICLES OF PIPER BETLE

Objective: The objective of the current study is toward the green synthesis of silver nanoparticles from the aqueous leaf extracts of Piper betle (BL) and to evaluate its anti-diabetic efficacy. Methods: Silver nanoparticles were prepared with the aqueous leaf extract of Piper betle. Characterization of silver nanoparticles prepared from extracts of Piper betle was done by UV-Visible spectrophotometer absorbance spectrum; Scanning Electron Microscope; and Fourier transform infrared spectrophotometer. The anti-diabetic efficacy was ascertained by inhibition assay of α-amylase activity and glucose diffusion inhibitory study with aqueous leaf extract of Piper betle and silver nanoparticles of Piper betle (BLNP). Results: Based on the findings of spectrophotometer studies, it was confirmed that the silver nanoparticles were generated. High-density silver nanoparticles were synthesized by Piper betle was depicted by scanning electron microscope. The plant extracts (BLE) and its nanoformulation (BLNP) showed a constructive impact on controlling the glucose level by the inhibition of α-amylase activity and glucose diffusion. Conclusion: It was concluded that the Piper betle can be employed as alternative medicine in the efficient management of Diabetes Mellitus.

Controllable in situ synthesis of silver nanoparticles on multilayered film-coated silk fibers for antibacterial application

Layer-by-layer (LbL) assembly is a versatile technique for the preparation of multilayered polymeric films. However, fabrication of LbL polymetic film on silk for the in situ growth of high-density silver nanoparticles (AgNPs) has not been realized. Herein poly(acrylic acid) (PAA)/poly(dimethyldiallylammonium chloride) (PDDA) multilayers are constructed on silk via the LbL approach, subsequently serving as a 3-dimensional matrix for in situ synthesis of AgNPs. After 8 rounds of LbL assembly, the silk is fully covered with a layer of polymeric film. AgNPs with good crystalline structures could be in-situ generated in the silk-coated multilayers and their amount could be tailored by adjusting the bilayer numbers. The as-prepared silk could effectively kill the existing bacteria and inhibit the bacterial growth, demonstrating the antimicrobial activity. Moreover, the release of Ag+ from the modified silk can last for 120h, rendering the modified silk sustainable antimicrobial activity. This work may provide a novel method to prepare AgNPs-functionalized antimicrobial silk for potential applications in textile industry.

Synthesis of uniform and high-density silver nanoparticles by using Peltophorum pterocarpum plant extract

Biologically synthesized nanoparticles have been widely used in the field of medicine. In this present work stable colloidal silver nanoparticles are prepared by a simple cost-effective, facile, and ecofriendly synthesis method to avoid the use of toxic chemicals. Peltophorum pterocarpum (PP) plant extract was employed to serve as both reducing and capping agents in this reaction. The effect of different experimental parameters such as the concentration of silver ions, the dosage of the plant extract, temperature, and reaction time on the synthesis of nanoparticles were studied. The synthesized nanoparticles were characterized using ultraviolet–visible (UV–vis) spectroscopy, X-ray diffractometry (XRD), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FT-IR), which revealed the nature of the nanoparticles. The nanoparticles have different diameters ranging from 40 to 85 nm. By optimizing the experimental conditions, more uniform high-density nanoparticles can be achieved. The synthesized silver nanoparticles exhibit significant antibacterial activity on gram-positive Staphylococcus aureus. The silver nanoparticles prepared in this way are uniform and stable, which can be stored at room temperature for more than two months.

Synthesis of Uniform and High Density Silver Nanoparticles by using Peltophorum pterocarpum flower Extract

ABSTRACTSilver nanoparticle (AgNP) is one of the elegant material because its uses in various fields. In this study, AgNPs have been prepared by using Peltophorum pterocarpum (PP) flower extract as reducing and capping agent and aqueous silver nitrate (aq.AgNO3) as silver precursor. The synthesized nanoparticles were characterized using Ultra Violet - Visible (UV-Vis) spectroscopy, High Resolution Transmission Electron Microscope (HR-TEM) and Fourier Transform Infrared Spectroscopy (FT-IR), which reveals the formation of nanosized particles. The UV-Vis spectrum shows an absorption peak around 430nm. HR-TEM images of AgNPs with clear morphology and well dispersed prepared AgNPs.

Fabrication of high-density silver nanoparticles on the surface of alginate microspheres for application in catalytic reaction

High-density silver nanoparticles immobilized on the surface of alginate microspheres exhibit excellent catalytic activity by reduction of p-nitrophenol.

Nanosilver Particle Formation on a High Surface Area Titanate

Titanium based molecular sieves, such as ETS-10, have the ability to exchange silver ions and subsequently support self assembly of stable silver nanoparticles when heated. We report that a high surface area sodium titanate (resembling ETS-2) displays a similar ability to self template silver nanoparticles on its surface. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show high concentrations of silver nanoparticles on the surface of this sodium titanate, formed by thermal reduction of exchanged silver cations. The nanoparticles range in size from 4 to 12 nm, centered at around 6 nm. In addition to SEM and TEM, XRD and surface area analysis were used to characterize the material. The results indicate that this sodium titanate has a high surface area (>263 m2/g), and high ion exchange capacity for silver (30+ wt%) making it an excellent substrate for the exchange and generation of uniform, high-density silver nanoparticles.

High-Density Silver Nanoparticle Film with Temperature-Controllable Interparticle Spacing for a Tunable Surface Enhanced Raman Scattering Substrate

The formation of high-density silver nanoparticles and a novel method to precisely control the spacing between nanoparticles by temperature are demonstrated for a tunable surface enhanced Raman scattering substrates. The high-density nanoparticle thin film is accomplished by self-assembling through the Langmuir-Blodgett (LB) technique on a water surface and transferring the particle monolayer to a temperature-responsive polymer membrane. The temperature-responsive polymer membrane allows producing a dynamic surface enhanced Raman scattering substrate. The plasmon peak of the silver nanoparticle film red shifts up to 110 nm with increasing temperature. The high-density particle film serves as an excellent substrate for surface-enhanced Raman spectroscopy (SERS), and the scattering signal enhancement factor can be dynamically tuned by the thermally activated SERS substrate. The SERS spectra of Rhodamine 6G on a high-density silver particle film at various temperatures is characterized to demonstrate the tunable plasmon coupling between high-density nanoparticles.

Formation and characterization of high-density silver nanoparticles embedded in silica thin films by “in situ” self-reduction

Silver nanoparticles (10–20 nm) embedded into silica thin films have been obtained through the use of a silver organometallic precursor compound dissolved in Spin-On-Glass and subsequently spinned onto suitable substrates. In this paper we present a study of the shape, size, and distribution of silver particles through the use of microscopes, x-ray diffraction, and optical extinction. It has been observed that the obtained films are stable for annealing up to 500 °C with a progressive degradation above this temperature. Furthermore it is possible to obtain high-density silver particles up to 15% in weight without affecting the cluster size and shape.