In the present study, first time we report the microwave-assisted green synthesis of silver nanoparticles (AgNPs) using Tamarindus indica natural fruit extract. The plant extract plays a dual role of reducing and capping agent for the synthesis of AgNPs. The formation of spherical shape AgNPs is confirmed by XRD, HR-SEM, and HR-TEM. The presence of face-centered cubic (FCC) silver is confirmed by XRD studies and the average crystallite size of AgNPs is calculated to be around 6–8 nm. The average particle diameter is found to be around 10 nm, which is identified from HR-TEM images. The purity of AgNPs is confirmed by EDX analysis. The presence of sigmoid curve in UV–Visible absorption spectra suggests that the reaction has complicated kinetic features. To investigate the functional groups of the extract and their involvement in the reduction of AgNO3 to form AgNPs, FT-IR studies are carried out. The redox peaks are observed in cyclic voltammetry in the potential range of − 1.2 to + 1.2 V, due to the redox active components of the T. indica fruit extract. In photoluminescence spectroscopy, the excited and emission peaks were obtained at 432 nm and 487 nm, respectively. The as-prepared AgNPs showed good results towards antibacterial activities. Hence, the present approach is a facile, cost- effective, reproducible, eco-friendly, and green method. © 2017

John Kennedy L

Physics

School of Advanced Sciences

Chennai Campus

Vijaya J.J

Kaviyarasu K

Kombaiah K

Ramalingam R.J

Munusamy M.A

Al-Lohedan H.A.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Journal of Photochemistry and Photobiology B: Biology

In the present study, we report the green synthesis of NiO nanoparticles using Aegle marmelos as a fuel and this method is ecofriendly and cost effective. The plant Aegle marmelos is used in the field of pharmaceuticals to cure diseases like chronic diarrhea, peptic ulcers and dysentery in India for nearly 5 centuries. The as-prepared nanoparticles were confirmed as pure face centered cubic phase and single crystalline in nature by XRD. The formation of agglomerated spherical nanoparticles was shown by HR-SEM and HR-TEM images. The particle size calculated from HR-SEM was in the range 8–10 nm and it matches with the average crystallite size calculated from the XRD pattern. NiO shows intense emission peaks at 363 and 412 nm in its PL spectra. The band gap of 3.5 eV is observed from DRS studies and the formation of pure Ni–O is confirmed by FT-IR spectra. The as-prepared NiO nanoparticles show super paramagnetic behavior, when magnetization studies are carried out. It is then evaluated for cytotoxic activity towards A549 cell culture, antibacterial activity and photocatalytic degradation (PCD) of 4‑chlorophenol (4‑CP), which is known as the endocrine disrupting chemical (EDC). From the results, it is found that the cell viability of A549 cells was effectively reduced and it showed better antibacterial activity towards gram positive bacterial strains. It is also proved to be an efficient and stable photocatalyst towards the degradation of 4‑CP. © 2018 Elsevier B.V.

Green synthesis of NiO nanoparticles using Aegle marmelos leaf extract for the evaluation of in-vitro cytotoxicity, antibacterial and photocatalytic properties

Green synthesis of silver nanoparticles (Ag NPs) using an extract of dried Zingiber officinale (ginger) root as a reducing and capping agent in the presence of microwave irradiation was herein reported for the first time. The formation of symmetrical spheres is confirmed from the UV–Visible spectrum of Ag NPs. Fourier transform infra-red spectroscopy confirms the formation of the Ag NPs. X-ray diffraction analysis was utilized to calculate the crystallite size of Ag NPs and the value was found to be 10 nm. High-resolution transmission electron microscopy and high-resolution scanning electron microscopy were used to investigate the morphology and size of the synthesized samples. The sphere like morphology is confirmed from the images. The purity and crystallinity of Ag NPs is confirmed by energy-dispersive X-Ray analysis and selected area electron diffraction respectively. The electrochemical behavior of the synthesized Ag NPs was assessed by cyclic voltammetry (CV) and shows the redox peaks in the potential range of − 1.1 to + 1.1 V. Agar diffusion method is used to examine the antibacterial activity of Ag NPs. For this purpose, two gram positive and two gram negative bacteria were studied. This single step approach was found to be simple, short time, cost-effective, reproducible, and eco-friendly. © 2017

Bioreduction potentials of dried root of Zingiber officinale for a simple green synthesis of silver nanoparticles: Antibacterial studies

Journal of Nanoscience and Nanotechnology

Preparation, Characterization and Structure Prediction of In2SnO3 and Spectroscopic (FT-IR, FT-Raman, NMR and UV-Visible) Study Using Computational Approach

A simple one-step rapid green microwave irradiation method is described for the synthesis of silver nanospheres (Ag NS) using threonine as a reducing and polyvinyl-pyrrolidone as a capping agent. UV-Visible spectrum and photoluminescence spectrum confirmed the formation of Ag NS. High-resolution transmission electron microscopy and high-resolution scanning electron microscopy was used to find the morphology of the synthesized sample, which has sphere-like morphology. The elemental composition of the Ag NS was determined by energy dispersive X-ray analysis. Antibacterial experiments showed that the prepared Ag NS had better antibacterial activities than silver nitrate in the same concentration. © 2015 Taylor and Francis Group, LLC.

Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry

Microwave-Assisted Rapid Facile Synthesis, Characterization, and Their Antibacterial Activity of PVP Capped Silver Nanospheres

Silver nanoparticles (Ag NPs) were synthesized by a simple microwave irradiation method using polyvinyl pyrrolidone (PVP) as a capping agent and serine as a reducing agent. UV-Visible spectra were used to confirm the formation of Ag NPs by observing the surface plasmon resonance (SPR) band at 443nm. The emission spectrum of Ag NPs showed an emission band at 484nm. In the presence of microwave radiation, serine acts as a reducing agent, which was confirmed by Fourier transformed infrared (FT-IR) spectrum. High-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning electron microscopy (HR-SEM) were used to investigate the morphology of the synthesized sample. These images showed the sphere-like morphology. The elemental composition of the sample was determined by the energy dispersive X-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NPs. The electrochemical behavior of the synthesized Ag NPs was analyzed by the cyclic voltammetry (CV). Antibacterial experiments showed that the prepared Ag NPs showed relatively similar antibacterial activities, when compared with AgNO3 against Gram-positive and Gram-negative bacteria.

Materials Science and Engineering: C

Antibacterial activity of silver nanoparticles synthesized from serine

One step phytosynthesis of highly stabilized silver nanoparticles (AgNPs) had been produced by using the extract of Piper nigrum (black pepper) as a reducing and a capping agent in aqueous medium, without the addition of any other chemicals. UV-visible (UV-vis) spectra showed the formation of AgNPs by observing the surface plasmon resonance (SPR) band at 444 nm. X-ray diffraction (XRD) analysis confirmed the formation of AgNPs with face centered cubic (fcc) structure. Fourier transform infra-red (FT-IR) spectra were used to identify the functional groups present in the biomolecules for reduction and capping of AgNPs. The electrochemical behaviour was carried out by cyclic voltammetry (CV). Oval-like morphology of the sample was confirmed by high-resolution scanning electron microscopy (HR-SEM) and high-resolution transmission electron microscopy (HR-TEM). Elemental composition was found out by the energy dispersive X-ray analysis (EDX). The antibacterial activities were carried out and revealed good results. This phytosynthetic approach is facile, inexpensive, reproducible, and eco-friendly. © 2014 Elsevier B.V.

Materials Letters

One step phytosynthesis of highly stabilized silver nanoparticles using Piper nigrum extract and their antibacterial activity

In this article, we report the synthesis of silver nanospheres (Ag NS) by a simple microwave irradiation method using Triton X 100 (TX 100) as a capping agent. TX 100 was also observed to act as a reducing agent in the presence of microwave radiation. From the ultraviolet-visible spectrum, the formation of Ag NS was confirmed by observing surface plasmon resonance band at 414 nm. The emission band of Ag NS was observed at 482 nm from the photoluminescence (PL) spectrum. High-resolution transmission electron microscopy (HR TEM) was used to investigate the morphology of the synthesized sample. It shows that the synthesized sample has sphere-like morphology with an average diameter of 5 nm. Further, the elemental composition of the Ag NS was determined by energy dispersive x-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NS. The interaction between Ag NS and TX 100 was established by Raman spectroscopy. The electrochemical behaviour of the synthesized Ag NS was analyzed by cyclic voltammetry (CV). © 2013 Copyright Taylor and Francis Group, LLC.

Journal of Dispersion Science and Technology

Microwave-Assisted Synthesis and Characterization of Triton X 100 Capped Silver Nanospheres

In the present study, silver nanoparticles were rapidly synthesized at room temperature by treating silver ions with the Citrus limon (lemon) extract. The effect of various process parameters like the reductant concentration, mixing ratio of the reactants and the concentration of silver nitrate were studied in detail. In the standardized process, 10(-2)M silver nitrate solution was interacted for 4h with lemon juice (2% citric acid concentration and 0.5% ascorbic acid concentration) in the ratio of 1:4 (vol:vol). The formation of silver nanoparticles was confirmed by Surface Plasmon Resonance as determined by UV-Visible spectra in the range of 400-500 nm. X-ray diffraction analysis revealed the distinctive facets (111, 200, 220, 222 and 311 planes) of silver nanoparticles. We found that citric acid was the principal reducing agent for the nanosynthesis process. FT-IR spectral studies demonstrated citric acid as the probable stabilizing agent. Silver nanoparticles below 50 nm with spherical and spheroidal shape were observed from transmission electron microscopy. The correlation between absorption maxima and particle sizes were derived for different UV-Visible absorption maxima (corresponding to different citric acid concentrations) employing "MiePlot v. 3.4". The theoretical particle size corresponding to 2% citric acid concentration was compared to those obtained by various experimental techniques like X-ray diffraction analysis, atomic force microscopy, and transmission electron microscopy.

Journal	Data powered by TypesetJournal of Photochemistry and Photobiology B: Biology
Publisher	Data powered by TypesetElsevier BV
ISSN	1011-1344
Open Access	0