Green Biosynthesis Of Silver Nanoparticles Research Articles

Green Biosynthesis of Silver Nanoparticles by the Endophytic Fungus Fusarium oxysporum from Ginseng

Green Biosynthesis of Silver Nanoparticles by the Endophytic Fungus<i> Fusarium oxysporum</i> from Ginseng

Biological activities of silver nanoparticles from Nothapodytes nimmoniana (Graham) Mabb. fruit extracts

In the present investigation, we have described the green biosynthesis of silver nanoparticles (AgNPs) using ripened fruit aqueous extract of Nothapodytes nimmoniana (Graham) Mabb. as capping agent. The antioxidant, anticancer and antimicrobial activities of AgNPs were also studied. UV analysis revealed that AgNPs had a sharp peak at 416nm. X-ray diffraction (XRD) result confirmed the characteristic peaks indicated at 111, 200, 220 and 311 for the crystalline of the face centered cubic silver. The Scanning Electron Microscopy analysis results confirmed the spherical shaped of AgNPs with difference sizes of the particles and an average from 44 to 64nm. Further, fruit extract and AgNPs were evaluated total phenolic, tannin and flavonoid contents and were subjected to assess their antioxidant potential using various in vitro systems such as using 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), metal chelating, phosphomolybdenum and ferric reducing antioxidant power (FRAP) activities and antimicrobial activity against Bacillus subtilis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Escherichia coli. When compared to AgNPs, fruit extract exhibited uppermost radical scavenging activities. In addition, the cytotoxicity activity was determined by MTT assay. Our results clearly proved that biosynthesized AgNPs inhibited proliferation of HeLA cell line with an IC50 of 87.32±1.43μg/mL and antibacterial activity.

Green Biosynthesis of Silver Nanoparticles Using ‘Polygonum Hydropiper’ and Study its Catalytic Degradation of Methylene Blue

The green synthesis of silver nanoparticles with the small size and high stability paved the way to improve and protect the environment by decreasing the use of toxic chemicals and eliminating biological risks in biomedical applications. Plant mediated synthesis of silver nanoparticles is gaining more importance owing its simplicity, rapid rate of synthesis of nanoparticles and eco-friendliness. In this study, focus on biosynthesis of silver nanoparticles using Polygonum hydropiper extract and its catalytic degradation of hazardous dye, methylene blue has been highlighted. The rapid reduction of silver (Ag) ions was monitored using UV-Visible spectrophotometer and showed formation of silver nanoparticles within less than one hour with maximum absorption of silver nanoparticles at 430nm. The major functional groups present in the synthesis responsible for the formation of silver nanoparticles. It was identified by using Fourier Transform Infrared spectrophotometer (FTIR). Field Electron Scanning Microscope (FESEM) was used to characterise the nanoparticles synthesized using P.hydropiper. The morphology of silver nanoparticles was predominantly spherical and aggregated into irregular structure with average diameter of 60nm. In addition, this report emphasizes the effect of the silver nanoparticles on the degradation rate of hazardous dyes by sodium borohydride (NaBH4). The efficiency of silver nanoparticles as a promising candidate for the catalysis of organic dyes by NaBH4 through the electron transfer process is established in the present study.

Green Biosynthesis of Silver Nanoparticles Using Marine Red Algae Acanthophora specifera and its Antibacterial Activity

Silver has been known since ancient history for its antimicrobial property. Synthesis it by eco-friendly method is a good thing due to its cost effective, stability and environmentally favorable. In this study silver nanoparticles (AgNPs) were obtained by a green synthesis method. Alcoholic extraction of Acanthophora specifera was used to reduce silver nitrate salt to AgNPs. Structure of synthesized AgNPs which observed by the dark brown color development was characterized by X-Ray diffraction (XRD), where the crystalline nature of silver nanoparticles were cubic and its size was range in 33 nm to 81 nm. Moreover, infrared spectroscopy (FT-IR) was identified. Additionally, the anti-microbial activity of AgNPs was recorded by using disk diffusion methods. AgNPs significantly reduced the growth of both gram positive Staphylococcus aureus, Bacillus subtillis, and gram negative Salmonella spp., Escherichia coli in addition to the unicellular fungus Candida albicans.

Biogenic synthesis of silver nanoparticles using cell-free extract of Bacillus safensis LAU 13: antimicrobial, free radical scavenging and larvicidal activities

AbstractThe cell-free extract of Bacillus safensis LAU 13 strain (GenBank accession No: KJ461434) was used for green biosynthesis of silver nanoparticles (Ag-NP

Green biosynthesis of silver nanoparticles using Calliandra haematocephala leaf extract, their antibacterial activity and hydrogen peroxide sensing capability

In recent times, plant-mediated synthesis of nanoparticles has garnered wide interest owing to its inherent features such as rapidity, simplicity, eco-friendliness and cheaper costs. For the first time, silver nanoparticles were successfully synthesized using Calliandra haematocephala leaf extract in the current investigation. The as-formed silver nanoparticles were characterized by UV–Vis spectrophotometer and the characteristic surface plasmon resonance peak was identified to be 414nm. The morphology of the silver nanoparticles was characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) was used to detect the presence of elemental silver. X-ray diffraction (XRD) was employed to ascertain the crystalline nature and purity of the silver nanoparticles which implied the presence of (111) and (220) lattice planes of the face centered cubic (fcc) structure of metallic silver. Fourier transform infrared spectroscopy (FTIR) was used to key out the specific functional groups responsible for the reduction of silver nitrate to form silver nanoparticles and the capping agents present in the leaf extract. The stability of the silver nanoparticles was analyzed by zeta potential measurements. A negative zeta potential value of −17.2mV proved the stability of the silver nanoparticles. The antibacterial activity against Escherichia coli – pathogenic bacteria – and the capacity to detect hydrogen peroxide by the silver nanoparticles were demonstrated which would find applications in the development of new antibacterial drugs and new biosensors to detect the presence of hydrogen peroxide in various samples respectively.

Green biosynthesis of silver nanoparticles using Torreya nucifera and their antibacterial activity

Silver nanoparticles were biosynthesized with the aid of a novel and eco-friendly biological material Torreya nucifera. Temperature and extract concentration were found to influence the size and shape of the biosynthesized silver nanoparticles. Morphological images of biosynthesized nanomaterials revealed that the particles are in spherical shape and size ranging between 10 and 125nm. Crystalline nature of nanoparticles in face centered cubic (fcc) structure was ensured by diffraction pattern peaks corresponding to (111), (200), (220) and (311) planes. Characterization of the biosynthesized nanoparticles was performed by the X-ray diffraction and Fourier Transform Infrared spectroscopy analyses. FT-IR analysis indicates that nanoparticles are bound to proteins through amine groups of the aminoacid. Furthermore the biosynthesized nanoparticles were found to be highly effective against Salmonella typhimurium bacterium, which validates its potential applications as antibacterial agents in drinking water treatment and in food packagings.

Green biosynthesis of silver nanoparticles and nanomolar detection of p-nitrophenol

Green biosynthesis of nanoparticles and their applications in sensor field is of great interest to the researchers. We report herein a simple green approach for the synthesis of silver nanoparticles (Ag-NPs) using Acacia nilotica Willd twig bark and its application for the detection of 4-nitro phenol (4-NP). The synthesized Ag-NPs were characterized by Transmission electron microscopy, X-ray diffraction and elemental analysis. The size of synthesized Ag-NPs was in the range of 10–50 nm. The Ag-NPs modified electrode shows a high sensitivity and selectivity towards the sensing of 4-NP. The fabricated modified electrode shows a low detection limit of 15 nM on the wider linear response range from 100 nM to 350 μM with the sensitivity of 2.58 ± 0.05 μAμM−1 cm−2. In addition, the fabricated sensor shows good repeatability and reproducibility.

Green biosynthesis of silver nanoparticles from Annona squamosa leaf extract and its in vitro cytotoxic effect on MCF-7 cells

The biological method for the synthesis of silver nanoparticles (AgNPs) using Annona squamosa leaf extract and its cytotoxicity against MCF-7 cells are reported. The synthesized AgNPs using A. squamosa leaf extract was determined by UV–visible spectroscopy and it was further characterized by FT-IR, X-ray diffraction (XRD), Transmission electron microscopy (TEM), Zeta potential and energy dispersive spectrometric (EDS) analysis. The UV–visible spectrum showed an absorption peak at 444nm which reflects surface plasmon resonance (SPR) of AgNPs. TEM photography showed biosynthesized AgNPs were predominantly spherical in shape with an average size ranging from 20 to 100nm. The Zeta potential value of −37mV revealed the stability of biosynthesized AgNPs. Furthermore, the green synthesized AgNPs exhibited a dose-dependent cytotoxicity against human breast cancer cell (MCF-7) and normal breast epithelial cells (HBL-100) and the inhibitory concentration (IC50) were found to be 50μg/mL, 30μg/mL, and 80μg/mL, 60μg/ml for AgNPs against MCF-7 and normal HBL-100 cells at 24h and 48h incubation respectively. An induction of apoptosis was evidenced by (AO/EtBr) and DAPI staining. Application of such eco-friendly nanoparticles makes this method potentially exciting for the large scale synthesis of nanoparticles.

Green Biosynthesis of Silver Nanoparticles Using Callicarpa maingayi Stem Bark Extraction

Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of silver nanoparticles using Callicarpa maingayi stem bark extract has been reported. Characterizations of nanoparticles were done using different methods, which include; ultraviolet-visible spectroscopy (UV-Vis), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) spectrometry, zeta potential measurements and Fourier transform infrared (FT-IR) spectroscopy. UV-visible spectrum of the aqueous medium containing silver nanoparticles showed absorption peak at around 456 nm. The TEM study showed that mean diameter and standard deviation for the formation of silver nanoparticles were 12.40 ± 3.27 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc) structure. The most needed outcome of this work will be the development of value added products from Callicarpa maingayi for biomedical and nanotechnology based industries.

Green biosynthesis of silver nanoparticles from an actinobacteria Rhodococcus sp.

The biosynthesis of nanoparticles has been proposed as a cost effective environmental friendly alternative to chemical and physical methods. Microbial synthesis of nanoparticles is a green chemistry approach that interconnects nanotechnology and microbial biotechnology. In this present study, synthesis of silver nanoparticles (AgNPs) has been demonstrated using a metabolically versatile actinobacteria Rhodococcus sp. by reducing aqueous silver nitrate. The AgNPs were characterized by Ultraviolet–Visible (UV–vis) Spectrometer, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX), Dynamic Light Scattering (DLS), Selected Area Diffraction Pattern (SAED) and Transmission Electron Microscopy (TEM). The TEM showed spherical particles with an average size of 10nm. The SAED pattern showed the characteristic Bragg peaks of (111), (200), (220) and (311) facets of the face centered cubic (fcc) silver nanoparticles and confirmed that these nanoparticles are crystalline in nature. The synthesis of AgNPs is a biosynthesis process where cell enzyme systems of Rhodococcus sp. may take part in synthesis process.

Green biosynthesis of silver nanoparticles using Curcuma longa tuber powder

Green synthesis of noble metal nanoparticles is a vastly developing area of research. Metallic nanoparticles have received great attention from chemists, physicists, biologists, and engineers who wish to use them for the development of a new-generation of nanodevices. In this study, silver nanoparticles were biosynthesized from aqueous silver nitrate through a simple and eco-friendly route using Curcuma longa tuber-powder extracts, which acted as a reductant and stabilizer simultaneously. Characterizations of nanoparticles were done using different methods, which included ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray fluorescence spectrometry, and Fourier-transform infrared spectroscopy. The ultraviolet-visible spectrum of the aqueous medium containing silver nanoparticles showed an absorption peak at around 415 nm. Transmission electron microscopy showed that mean diameter and standard deviation for the formation of silver nanoparticles was 6.30 ± 2.64 nm. Powder X-ray diffraction showed that the particles are crystalline in nature, with a face-centered cubic structure. The most needed outcome of this work will be the development of value-added products from C. longa for biomedical and nanotechnology-based industries.