• Toxicological Research
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• 제30권3호
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• pp.169-178
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• 2014

This review covers general information regarding the green synthesis of antibacterial silver nanoparticles. Owing to their antibacterial properties, silver nanoparticles are widely used in many areas, especially biomedical applications. In green synthesis practices, the chemical reducing agents are eliminated, and biological entities are utilized to convert silver ions to silver nanoparticles. Among the various biological entities, natural plant extracts have emerged as green reducing agents, providing eco-friendly routes for the preparation of silver nanomaterials. The most obvious merits of green synthesis are the increased biocompatibility of the resulting silver nanoparticles and the ease with which the reaction can be carried out. This review summarizes some of the plant extracts that are used to produce antibacterial silver nanoparticles. Additionally, background information regarding the green synthesis and antibacterial activity of silver nanoparticles is provided. Finally, the toxicological aspects of silver nanoparticles are briefly mentioned.

• Advances in nano research
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• 제10권1호
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• pp.71-76
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• 2021

Synthesis of nanoparticles using green technology using plants is gaining significant attention as it is an environmentally friendly substitute to conventional physical and chemical methods. The present study was focused on the chemical and green synthesis of Iron Oxide nanoparticles from ferric chloride. The green synthesis was achieved by utilizing the bio components of Hibiscus rosa-sinensis. The Fe3O4 nanoparticles with the size range of 87-400 nm were synthesized by wet chemical reduction technique which are unstable, prone to aggregation while in green synthesis the phytochemicals present in the leaf extract acts as the capping as well as the reducing agent thus the green synthesized iron (III) oxide nanoparticles were naturally stabilized, spherical shaped and are in the size range of 2-80 nm. The results of both the protocols are compared and presented briefly.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2609-2612
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• 2012

A simple green method was developed for rapid synthesis of silver and gold nanoparticles (AgNPs and AuNPs) has been reported using Lonicera japonica flower extract as a reducing and a capping agent. AgNPs and AuNPs were carried out at $70^{\circ}C$. The successful formation of AgNPs and AuNPs have been confirmed by UV-Vis spectro photometer, fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray Analysis (EDAX), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). To our knowledge, this is the first report where Lonicera japonica flower was found to be a suitable plant source for the green synthesis of AgNPs and AuNPs.

• 한국환경과학회지
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• 제26권2호
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• pp.239-248
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• 2017

Green synthesis of gold nanoparticles(GNPs) considered more ecofriendly and cost effective than other chemical methods use of dangerous reagents and solvents, improved material and energy efficiency and enhanced design of non-toxic products. In this study, we developed a green synthesis method for using Caulis in Taeniam (BCT). BCT were characterized by UV-vis, Zetasizer, TEM, XRD, and FTIR. The antioxidant activity of BCT was determined by DPPH and ABTS radical-scavenging assays, and heme oxygenase-1 induction in RAW 264.7 macrophages. The resulting BCT appeared spherical with an average diameter of 67.171.39 nm The aAntioxidant activity was increased in a dependent manner. To conclude, the green synthesis of BCT-GNPs was successful, and it appers to be useful in the for future applications.

• Nano
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• 제13권11호
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• pp.1850132.1-1850132.14
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• 2018

The direct synthesis of metal-organic frameworks (MOFs) with acidic and basic active sites is challenging due to the introduction of functional groups by post-functionalization method often jeopardize the framework integrity. Herein, we report the direct synthesis of acid-base bifunctional MOFs with tuning acid-base strength. Employing modulated hydrothermal (MHT) approach, microporous MOFs named $UiO-66-NH_2$ was prepared. Through the ring-opening reaction of 1,3-propanesultone with amino group, $UiO-66-NH_2-SO_3H-type$ catalysts can be obtained. The synthesized catalysts were well characterized and their catalytic performances were evaluated in one-pot glucose to 5-HMF conversion. Results revealed the acid-base bi-functional catalyst possessed high activity and excellent stability. This work provides a general and economically viable approach for the large-scale synthesis of acid-base bi-functional MOFs for their potential use in catalysis field.

• 대한화학회지
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• 제66권4호
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• pp.284-297
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• 2022

The antibacterial activity of metallic nanoparticles (NPs), especially silver (Ag), has been investigated during the course of time in various chemical reactions for antibiotics free agents. Green synthesis of metallic NPs using either microorganisms or plant-extracts has appeared as a simple and replacement to chemical and physical methods. The synthesizing of these NPs through ecofriendly methods signifies an exceedingly applicable approach for offering economical, preferring scalability and possessing negligible ecological influences. Essential-oils are among the subordinate metabolites of plants and their antibacterial anti-inflammatory characteristics have been investigated widely and are commonly attained from the aromatic plants. The usage of essential-oils as reducing agents in biosynthesizing of Ag NPs bring together the interaction of a vital antibacterial agent that simplify the nucleation and growth process within the NPs formation. This review article is offering a progressive process of Ag NPs synthesis using essential oils along with proposing the most applicable formation mechanisms and their antibacterial activities.

• 펄프종이기술
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• 제46권2호
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• pp.8-15
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• 2014

A novel antibacterial paper coated with chitosan-based silver (Ag) nanocomposite prepared by green synthesis has been investigated for a wide range of application in food, agricultural and medical packaging. Green synthesis of Ag nanoparticles (AgNPs) was carried out by a chemical reaction involving a mixture of chitosan-silver nitrate (AgNO3) in an autoclave at 15 psi, $121^{\circ}C$, for 15-120 sec. AgNPs and their formation in chitosan were confirmed by both UV-Vis spectroscopy and transmission electron microscope (TEM). Fourier transform infrared spectroscopy (FTIR) study showed that free amino groups in chitosan act as an effective reductant and AgNPs stabilizer. Antibacterial test of coated paper with as-prepared chitosan-AgNPs was performed qualitatively against E. coli based on the formation of halo zones around coated papers and it was shown to be effective in suppressing the growth of E. coli with increasing Ag contents in coating layer.

• Advances in nano research
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• 제11권6호
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• pp.657-665
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• 2021

The present work aimed to explore green approach via aqueous leaves extract of Murraya koenigii (ALEMk) for the synthesis of silver nanoparticles (AgNPsMk) in single step. The synthesis process was visualized with a color change and monitored by employing UV/Visible spectroscopy and a clear peak attained at 420 nm confirming the synthesis of AgNPsMk. The possible functional groups present in the extract which participated in the synthesis of AgNPsMk were identified with the help of FTIR spectroscopy. Further characterization using TEM images revealed the spherical shape of AgNPsMk with average particle size of 20 nm displaying well dispersion throughout the solution. Pronounced antioxidant activities of AgNPsMk at increased concentrations observed which evidencing strong radical scavenging ability. Moreover, AgNPsMk exhibited strong antibacterial behavior when tested against bacterial strains of Escherichia coli and Bacillus subtilis. Moving ahead, in vitro cytotoxicity work revealed potent cell viability loss appearing in AU565 and HeLa cancer cell lines on exposure to AgNPsMk at increased concentration. Finally, in vivo assessment carried out inside male Wistar rats indicated non toxic effect on examined liver tissues besides biochemical analysis including bilirubin, alkaline phosphtase (ALP) and serum glutamate pyruvate transaminase (SGPT) which found within the normal range when compared with control. The prior research work profoundly apprises the potential of green synthesized AgNPsMk to play a significant role in biomedical applications and formulations.

• Tribology and Lubricants
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• 제29권6호
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• pp.392-396
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• 2013

Biodiesel fuels contain unsaturated fatty acid ester, which can easily oxidize, especially when exposed to ultraviolet light. The products formed by this oxidation give rise to sediment or gum formation. As a result, the fuel can contribute to the corrosion and plugging of the filter pump. Antioxidants have been used in an effort to stabilize biodiesels, but there is still a need for a biodiesel composition with improved oxidation stability. In general, good fuel compositions should provide synergistic combinations of a biodiesel and antioxidants. Our work involved the synthesis of antioxidants to improve the oxidative stability of biodiesel fuel.

• Advances in nano research
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• 제2권3호
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• pp.135-145
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• 2014

Nanomaterials synthesized by natural bioresources such as microorganisms, animals and plants in nature can also be synthesized in laboratories even on large scale. This is considered as an attractive prospect for eco-friendly or so-called green synthesis. Development of eco-friendly synthesis of biocompatible nanoparticles and their potential biomedical applications introduces the concept of nanobiotechnology. The lower cost and lesser side effects as compare to chemical methods of synthesis are the main advantages of biosynthesis. This review article demonstrates the role of various biological resources e.g. bacteria, fungi, actinomycetes, plant leaves, fruits and honey as well as animal tissues for the synthesis of nanoparticles mainly gold and silver with an overview of their potential applications.