Plant extract mediated synthesis of metal nanoparticles, their characterization and applications: A green approach

2021 ◽  
Vol 08 ◽  
Author(s):  
Sudha Kumari Jha ◽  
Annapurna Jha

: Nowadays, nanoparticles are gaining enormous importance in a wide variety of disciplines due to their unambiguous physical and chemical properties. There are lots of physical and chemical approaches available for the synthesis of metal nanoparticles. But there are certain disadvantages associated with these methods, such as adsorption of hazardous toxins on the surface of the material, high capital investment, high manufacturing energy demand, etc., which make their effective implementation almost impossible. An alternative method of synthesizing nanoparticles to avoid the aforementioned disadvantages is to use different parts of the plant under aqueous conditions. Plant-mediated approach for the synthesis of nanoparticles is becoming increasingly popular due to its faster reaction rate, easily affordable, eco-friendly nature and rich diversity of plants. Chemical compositions of plant extracts are examined using the liquid chromatography-mass spectrometry technique. Noble metals such as Silver, Gold, Iron, Copper, Platinum, Zinc, Palladium, and their oxides are used for the fabrication of metal nanoparticles, due to their enormous potential applications. In a single-step green synthesis process, the phytochemical constituents which are present in plant extract reduce metal salts into metal nanoparticles. This article gives an overview of plant-mediated synthesized metal and metal oxide nanoparticles and their characterization by using different techniques, together with their properties and applications in numerous fields.

2021 ◽  
Vol 4 (3) ◽  
pp. 59
Author(s):  
Vinamra Bhushan Sharma ◽  
Kartik Singh ◽  
Ravi Gupta ◽  
Ayush Joshi ◽  
Rakesh Dubey ◽  
...  

There has been enormous growth in the energy sector in the new millennium, and it has enhanced energy demand, creating an exponential rise in the capital investment in the energy industry in the last few years. Regular monitoring of the health of industrial equipment is necessary, and thus, the concept of structural health monitoring (SHM) comes into play. In this paper, the purpose is to highlight the importance of SHM systems and various techniques primarily used in pipelining industries. There have been several advancements in SHM systems over the years such as Point OFS (optical fiber sensor) for Corrosion, Distributed OFS for physical and chemical sensing, etc. However, these advanced SHM technologies are at their nascent stages of development, and thus, there are several challenges that exist in the industries. The techniques based on acoustic, UAVs (Unmanned Aerial Vehicles), etc. bring in various challenges, as it becomes daunting to monitor the deformations from both sides by employing only one technique. In order to determine the damages well in advance, it is necessary that the sensor is positioned inside the pipes and gives the operators enough time to carry out the troubleshooting. However, the mentioned technologies have been unable to indicate the errors, and thus, there is the requirement for a newer technology to be developed. The purpose of this review manuscript is to enlighten the readers about the importance of structural health monitoring in pipeline and wind turbine industries.


2021 ◽  
Vol 11 (6) ◽  
pp. 304-314
Author(s):  
Anupama Singh ◽  
BLR Madhavi ◽  
M N Nithin Sagar

Nanoparticles in different field of science have a wide range of utility. They come in different forms. Among these, metal nanoparticles (MNP) have become an emerging tool for diagnostic as well as for therapeutic purposes. Metal nanoparticles are nano-sized particles made up of inorganic metals or their metal oxides. Various methods are available for the preparation/production of metal nanoparticles. In addition to the existing physical and chemical methods, green synthesis is an area that has drawn the attention of researchers in the decade and continues to be a potential area of research. The following review introduces about metal nanoparticles and discusses in details about the plant extract mediated metal nanoparticles synthesis, the principle of metal nanoparticle formation, various process parameters that are important for its synthesis, characterization of metal nanoparticles and the scope for commercialization are elaborated. Metal nanoparticles at research, employing plant extract mediated green synthesis have been extensively reviewed. This review tries to bring into light the feasibility of commercializing the green synthesis by using plant extracts. Keywords: Green synthesis; Plant extract; One-step synthesis; Characterization; Process parameters; Scale-up


2020 ◽  
Vol 26 (40) ◽  
pp. 5188-5204
Author(s):  
Uzair Nagra ◽  
Maryam Shabbir ◽  
Muhammad Zaman ◽  
Asif Mahmood ◽  
Kashif Barkat

Nanosized particles, with a size of less than 100 nm, have a wide variety of applications in various fields of nanotechnology and biotechnology, especially in the pharmaceutical industry. Metal nanoparticles [MNPs] have been synthesized by different chemical and physical procedures. Still, the biological approach or green synthesis [phytosynthesis] is considered as a preferred method due to eco-friendliness, nontoxicity, and cost-effective production. Various plants and plant extracts have been used for the green synthesis of MNPs, including biofabrication of noble metals, metal oxides, and bimetallic combinations. Biomolecules and metabolites present in plant extracts cause the reduction of metal ions into nanosized particles by one-step preparation methods. MNPs have remarkable attractiveness in biomedical applications for their use as potential antioxidant, anticancer and antibacterial agents. The present review offers a comprehensive aspect of MNPs production via top-to-bottom and bottom-to-top approach with considerable emphasis on green technology and their possible biomedical applications. The critical parameters governing the MNPs formation by plant-based synthesis are also highlighted in this review.


Nanomaterials ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1463 ◽  
Author(s):  
Vishma Pratap Sur ◽  
Marketa Kominkova ◽  
Zaneta Buchtova ◽  
Kristyna Dolezelikova ◽  
Ondrej Zitka ◽  
...  

The physical and chemical synthesis methods of quantum dots (QDs) are generally unfavorable for biological applications. To overcome this limitation, the development of a novel “green” route to produce highly-fluorescent CdSe QDs constitutes a promising substitute approach. In the present work, CdSe QDs were biosynthesized in yeast Saccharomyces cerevisiae using a novel method, where we showed for the first time that the concentration of tryptone highly affects the synthesis process. The optimum concentration of tryptone was found to be 25 g/L for the highest yield. Different methods were used to optimize the QD extraction from yeast, and the best method was found to be by denaturation at 80 °C along with an ultrasound needle. Multiple physical characterizations including transmission electron microscopy (TEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDX), and spectrophotometry confirmed the optical features size and shape distribution of the QDs. We showed that the novel conjugate of the CdSe QDs and a cell-penetrating peptide (hecate) can detect bacterial cells very efficiently under a fluorescent microscope. The conjugate also showed strong antibacterial activity against vancomycin-resistant Staphylococcus aureus (VRSA), methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli, which may help us to cope with the problem of rising antibiotic resistance.


2021 ◽  
pp. 0958305X2198988
Author(s):  
Nur Syakirah Rabiha Rosman ◽  
Noor Aniza Harun ◽  
Izwandy Idris ◽  
Wan Iryani Wan Ismail

The emergence of technology to produce nanoparticles (1 nm – 100 nm in size) has drawn significant researchers’ interests. Nanoparticles can boost the antimicrobial, catalytic, optical, and electrical conductivity properties, which cannot be achieved by their corresponding bulk. Among other noble metal nanoparticles, silver nanoparticles (AgNPs) have attained a special emphasis in the industry due to their superior physical, chemical, and biological properties, closely linked to their shapes, sizes, and morphologies. Proper knowledge of these NPs is essential to maximise the potential of biosynthesised AgNPs in various applications while mitigating risks to humans and the environment. This paper aims to critically review the global consumption of AgNPs and compare the AgNPs synthesis between conventional methods (physical and chemical) and current trend method (biological). Related work, advantages, and drawbacks are also highlighted. Pertinently, this review extensively discusses the current application of AgNPs in various fields. Lastly, the challenges and prospects of biosynthesised AgNPs, including application safety, oxidation, and stability, commercialisation, and sustainability of resources towards a green environment, were discussed.


2011 ◽  
Vol 382 ◽  
pp. 372-374
Author(s):  
Yong Jiang ◽  
Zhi Bin Jiang ◽  
Guo Jie Shao ◽  
Dong Cheng Guo ◽  
Yu Tian ◽  
...  

Purpose: The purpose of this study was to study the compositions of the polygonaceae medicinal plants called rumex root. Methods: Solvent method and chromatography was used to purificate the chemical compositions of Rumex, and the molecular structure of the compound was identified by physical and chemical properties and spectral data. Results: Two compounds were obtained from the ethanol extract of rumex root, which were identified as Chrysophanol and Physcione. Conclusions: Experimental basis was provided for the further study of the active ingredients of rumex root and the development and utilization of medical resources.


1982 ◽  
Vol 62 (1) ◽  
pp. 69-76 ◽  
Author(s):  
ANDRÉ FORTIN

Thirty-two Yorkshire pigs, 16 barrows and 16 gilts, were slaughtered at four weights (85, 92, 103 and 112 kg) to determine the effect of body weight at slaughter on the physical and chemical composition of the carcass. The right side was dissected into meat (including intra- and intermuscular fat), separable fat and bone which were subsequently analyzed for moisture, protein (N × 6.25), ether extract and ash. Sex did not influence (P < 0.05) carcass composition at any of the four slaughter weights. Increasing slaughter weight did not markedly alter the meat percentage of the carcass side but decreased the percentage of bone (P < 0.01). A trend toward an increasing percentage of separable fat was confirmed by the use of the allometric function Y = aXb. The effect of slaughter weight was more pronounced on the chemical than on the physical composition of the carcass side especially with respect to protein percentage. The chemical compositions of the meat, separable fat and bone were also determined. The protein percentage of each of the three physically separable components of the carcass side decreased (P < 0.01) with increasing slaughter weight. The partitioning of the chemically determined components among meat, separable fat and bone was not influenced by sex or by slaughter weight. Key words: Carcass composition, swine, sex, slaughter weight


2016 ◽  
Vol 9 (3) ◽  
pp. 357-394 ◽  
Author(s):  
I. F. Torres ◽  
T. Andrade

ABSTRACT Currently, there is an awareness that is critical to assess the durability characteristics of concrete with as much attention as the mechanical properties. The durability of concrete structures can often be affected by chemical attacks, jeopardizing its performance and security. When concrete is subjected to high temperature at early ages, many physical and chemical changes in hardened concrete may occur. It iswidely accepted that concrete subjected to these conditions of temperature and exposed to moisture is prone to cracking due to Delayed Ettringite Formation (DEF). This work aims at providing a DEF risk analysis on foundation pile caps at the Metropolitan Region of Recife - PE. Temperature rise measurement was performed in situ at 5 different caps through datalogger and thermocouples equipments. Furthermore, the Duggan test was performed in order to assess the level of expansion of 3 cements studied: X (CP II E 40), Y (CP II F 32) and Z (CP V ARI RS). Simultaneously, the chemical compositions of these cements and their respective clinkers were quantified by analysis of X-ray fluorescence (XRF). The cement X (CP II E 40) showed the chemical characteristics favoring with more intensity DEF and, as a result, higher level of expansion in the test Duggan. It is noteworthy that incorporation of metakaolin (8% and 16%) and silica fume (5% and 10%) showed mitigating potential of expansions. It is important to point out that all factors related to thermal properties and chemical composition of the concrete used in the region converge to a condition of ideal susceptibility for triggering DEF. Therefore, it is essential at least minimum and basic requirements in the design specification in order to avoid high temperatures in the massive concrete elements, preventing them from delayed ettringite formation.


2018 ◽  
Vol 9 ◽  
pp. 2763-2774 ◽  
Author(s):  
Alexander Rostek ◽  
Marina Breisch ◽  
Kevin Pappert ◽  
Kateryna Loza ◽  
Marc Heggen ◽  
...  

For a comparative cytotoxicity study, nanoparticles of the noble metals Rh, Pd, Ag, Pt, and Au (spherical, average diameter 4 to 8 nm) were prepared by reduction in water and colloidally stabilized with poly(N-vinyl pyrrolidone) (PVP). Thus, their shape, size, and surface functionalization were all the same. Size and morphology of the nanoparticles were determined by dynamic light scattering (DLS), analytical disc centrifugation (differential centrifugal sedimentation, DCS), and high-resolution transmission electron microscopy (HRTEM). Cell-biological experiments were performed to determine the effect of particle exposure on the viability of human mesenchymal stem cells (hMSCs). Except for silver, no adverse effect of any of the metal nanoparticles was observed for concentrations up to 50 ppm (50 mg L−1) incubated for 24 h, indicating that noble metal nanoparticles (rhodium, palladium, platinum, gold) that do not release ions are not cytotoxic under these conditions.


Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2412
Author(s):  
Francisco Ruiz-Jorge ◽  
Almudena Benítez ◽  
M. Belén García-Jarana ◽  
Jezabel Sánchez-Oneto ◽  
Juan R. Portela ◽  
...  

Lithium-ion batteries (LIBs) have gained much interest in recent years because of the increasing energy demand and the relentless progression of climate change. About 30% of the manufacturing cost for LIBs is spent on cathode materials, and its level of development is lower than the negative electrode, separator diaphragm and electrolyte, therefore becoming the “controlling step”. Numerous cathodic materials have been employed, LiFePO4 being the most relevant one mainly because of its excellent performance, as well as its rated capacity (170 mA·h·g−1) and practical operating voltage (3.5 V vs. Li+/Li). Nevertheless, producing micro and nanoparticles with high purity levels, avoiding the formation of iron oxides, and reducing the operating cost are still some of the aspects still to be improved. In this work, we have applied two heating rates (slow and fast) to the same hydrothermal synthesis process with the main objective of obtaining, without any reducing agents, the purest possible LiFePO4 in the shortest time and with the lowest proportion of magnetite impurities. The reagents initially used were: FeSO4, H3PO4, and LiOH, and a crucial phenomenon has been observed in the temperature range between 130 and 150 °C, being verified with various techniques such as XRD and SEM.


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