Fabrication and characterization of gelatin stabilized silver nanoparticles under UV-Light (original) (raw)

Silver nanoparticles with gelatin nanoshells: photochemical facile green synthesis and their antimicrobial activity

Journal of Nanoparticle Research, 2011

In the current study, a facile green synthesis of silver-gelatin core-shell nanostructures (spherical, spherical/cubic hybrid, and cubic, DLS diameter: 4.1-6.9 nm) is reported via the wet chemical synthesis procedure. Sunlight-UV as an available reducing agent cause mild reduction of silver ions into the silver nanoparticles (Ag-NPs). Gelatin protein, as an effective capping/shaping agent, was used in the reaction to self-assemble silver nanostructures. The formation of silver nanostructures and their self-assembly pattern was confirmed by SEM, AFM, and TEM techniques. Further investigations were carried out using zetapotential, UV-Vis, FTIR, GPC, and TGA/DTG/DTA data. The prepared Ag-NPs showed proper and acceptable antimicrobial activity against three classes of microorganisms (Escherichia coli Gram-negative bacteria, Staphylococcus aureus Gram-positive bacteria, and Candida albicans fungus). The antibacterial and antifungal Ag-NPs exhibit good stability in solution and can be considered as promising candidates for a wide range of biomedical applications.

Green Synthesis of Silver Nanoparticles and the Study of Optical Properties

Nanomaterials and Nanotechnology, 2012

The synthesis of silver nanoparticles of varying size has been achieved using different molar concentrations of NaOH while the effect of changing the temperature has been studied. AgNO3, gelatine, glucose and NaOH are used as a silver precursor, stabilizer, reducing agent and accelerator respectively. The synthesized nanoparticles have been characterized by a FESEM study, X-ray diffractometry, Raman spectroscopy and UV-vis spectroscopy. The colloidal sols of the silver nanoparticles in a biopolymer gelatine show strong surface plasmon resonance absorption peaks. The visible photoluminescence emission from the synthesized silver nanocrystals has been recorded within the wavelength range of 400–600 nm under UV excitation. The synthesized nanoparticles may be extremely useful in making biosensor devices as well as for other applications.

Synthesis and characterization of silver nanoparticles

2007

Silver nanoparticles have received considerable attention due to their attractive physical and chemical properties. The surface plasmon resonance and large effective scattering cross section of individual silver nanoparticles make them ideal candidates for molecular labeling, where phenomena such as surface enhance Raman scattering (SERS) can be exploited. In addition, silver nanoparticles have recently been shown to be a promising antimicrobial material. In the present research silver colloid was produced by sodium citrate reduction. The colloidal silver was incorporated by dip-coating to the polymer substrate. X-Ray Fluorescence Spectroscopy (XRF), Atomic force microscopy (AFM), ultraviolet-visible spectroscopy (UV-VIS ) and SERS indicate that the produced structures include metallic crystalline silver nanoparticles. The surface plasmon resonance peak in absorption spectra of silver particles showed an absorption maximum at 420-500 nm. The silver - polymer nanocomposites structures with selective light properties as a result of plasmon resonance shifting in the UV-VIS wavelength region were produced.

Preparation of colloidal silver nanoparticles and structural characterization

2013

Colloidal silver nanoparticles were prepared by-irradiating Ag þ in aqueous solution in the presence of 2% polyvinyl pyrrolidone (PVP) as stabilising agent and ethyl alcohol as free radical (OH .) scavenger. The saturated conversion dose of Ag þ into Ag was determined by UV-Vis spectroscopy and the silver nanoparticles size was characterised by transmission electron microscopy. The influence of Ag þ concentration (1-50 mM) on the saturated conversion dose and average diameter of silver nanoparticles was investigated. Results showed that the saturated conversion dose was from 8 to 48 kGy and the silver particles size was in the range of 6-21 nm for Ag þ concentration from 1 to 50 mM. The effect of PVP molecular weight on silver particles size was studied as well.

Silver Nanoparticles: Synthesis, Properties, and Applications

Silver has been recognized as a nontoxic, safe inorganic antibacterial/antifungal agent used for centuries. Silver demonstrates a very high potential in a wide range of biological applications, more particularly in the form of nanoparticles. Environmentally friendly synthesis methods are becoming more and more popular in chemistry and chemical technologies and the need for ecological methods of synthesis is increasing; the aim is to reduce polluting reaction by-products. Another important advantage of green synthesis methods lies in its cost-effectiveness and in the abundance of raw materials. During the last five years, many efforts were put into developing new greener and cheaper methods for the synthesis of nanoparticles. The cost decrease and less harmful synthesis methods have been the motivation in comparison to other synthesis techniques where harmful reductive organic species produce hazardous by-products. This environment-friendly aspect has now become a major social issue and is instrumental in combatting environmental pollution through reduction or elimination of hazardous materials. This review describes a brief overview of the research on green synthesis of silver metal nanoparticles and the influence of the method on their size and morphology.

Silver Nanoparticles Synthesis, Properties, Applications and Future Perspectives: A Short Review

Silver nanoparticles (Ag NPs) have gained significant interest due to their unique optical, antimicrobial, electrical, physical properties and their possible application. The change of energy level from continuous band to discrete band of Ag NPs with decrease in size of particles gives strong size dependent chemical and physical properties. Ag NPs show lower toxicity to human health while Ag NPs show higher toxicity to various micro-organisms. For this reason Ag NPs having scope for medical instruments, antimicrobial application, products for health care such as scaffolds, burn dressing, water purification, agriculture uses. Ag NPs can be synthesized by using various methods which is primarily classified into two type’s namely physical process which includes laser ablation, condensation, evaporation etc. and chemical process which includes hydrazine, sodium borohydride, green synthesis etc. Among all these methods green synthesis is non-toxic, eco-friendly and cost effective. In this review paper different synthesis process especially green synthesis, properties, applications of silver nanoparticles and their recent advances are described. We also highlight the toxicity and compares Ag NPs with others nanoparticles.

Green synthesis and characterization of gelatin-based and sugar-reduced silver nanoparticles

International Journal of Nanomedicine, 2011

Silver nanoparticles (Ag-NPs) have been successfully prepared with simple and "green" synthesis method by reducing Ag + ions in aqueous gelatin media with and in the absence of glucose as a reducing agent. In this study, gelatin was used for the first time as a reducing and stabilizing agent. The effect of temperature on particle size of Ag-NPs was also studied. It was found that with increasing temperature the size of nanoparticles is decreased. It was found that the particle size of Ag-NPs obtained in gelatin solutions is smaller than in gelatin-glucose solutions, which can be related to the rate of reduction reaction. X-ray diffraction, ultravioletvisible spectra, transmission electron microscopy, and atomic force microscopy revealed the formation of monodispersed Ag-NPs with a narrow particle size distribution.

Biological Sciences SYNTHESIS AND CHARACTERIZATION OF SILVER NANOPARTICLES

2014

Silver nanoparticles exhibit new optical properties, which are observed neither in molecules nor in bulk metals. In the present study silver nanoparticle colloid was produced by chemical reduction method of silver salt (silver nitrate AgNO3) solution. The silver nanoparticles were characterized by using UV-VIS spectrometer and Scanning Electron Microscope (SEM). The Surface Plasmon Resonance peak in absorption spectra of silver colloidal solution showed an absorption maximum at 450 nm which indicated formation of silver nanoparticles. The size range 44nm to 56.55nm of silver nanoparticles was determined by using Scanning Electron Microscope (SEM). The absorbance range of prepared silver nanoparticles solution was checked on 1 st day, 5 th day, 18 th day and on 30 th day. There was no obvious change observed in peak position for 30 days, depicting the stability of Silver nanoparticles.

The Influence of Silver Nanoparticles Synthesis on Their Properties

Acta Polytechnica

Application of green methods to replace physical and chemical methods for synthesis of silver nanoparticles (AgNPs) has become necessary not only from economic aspect but especially due to its significant impact on ecosystem. The properties of biologically synthesized AgNPs using green algae Parachlorella kessleri (P. kessleri) and chemically prepared were investigated and compared. The UVvis analysis confirmed a high stability of biosynthesized AgNPs as well as chemically synthesized gelatin modified citrate-AgNPs. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) revealed different sizes and shapes of AgNPs synthesized in different ways. Biosynthesized AgNPs have similar inhibitory antimicrobial activity as gelatin/sodium citrate–AgNPs.