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Gold Nano Particles (GNPs): An Emerging Solution of Cancer

Gold Nano Particles (GNPs): An Emerging Solution of Cancer

Nanotechnology is not the simple technology of matters in reduced nanometer scale. Materials in the nanometer scale often exhibit some physical properties which is completely different from its bulk form. In US, nanotechnology has been defined as being “concerned with materials and systems whose structure and components exhibit novel and significantly improved physical, chemical and biological properties, phenomena and processes due to their Nano scale size” [7]. In general, nanotechnology deals with Nano materials, nanostructures and nanoparticles. Nano-materials are those which have structured component with at least one dimension less than 100 nm. A nanostructure is an atomic structure of Nano scale, size no longer than 100 nm. Particle satisfies this criterion is called nanoparticle. Nanoparticles’ usages have already been explored; for instance, Cerium Oxide nanoparticles act as an antioxidant in traumatic injury. Silicon Dioxide crystalline nanoparticles are now being used to strengthening tennis racquets. Carbon fibers, silver nanoparticles have usage in fabric like killing bacteria,
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Preparation and Characterization of Microfiltration Membrane Embedded with Silver Nano-Particles

Preparation and Characterization of Microfiltration Membrane Embedded with Silver Nano-Particles

Different types of “template methods” have been discussed by researchers for preparation of nano-tube membranes [12, 13]. This procedure may be carried out via various techniques including electrochemical deposition, sol-gel, chemical vapor deposition, chemical polymerization and electro-less plating. The latter is chemically covering the pores and the surface of a membrane by a desired material. This alters the properties of the membrane. Martin and coworkers produced gold nano-tubule membranes with both cation and anion permselectivity [14], chemical transport selectivity [15] or optical property [16]. The other researchers prepared silica/titania nanorods / nanotubes composite [17], carbon nano-tube [18] or silver nano-particle membranes. The template method is a general procedure for synthesis of nano-tubes, nano-cables and nano-rods [20-28].
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Eco-friendly organic – inorganic 
										technique for the production of 
										nano-particles of precious metals like 
										gold and silver for medical and research 
										purposes.

Eco-friendly organic – inorganic technique for the production of nano-particles of precious metals like gold and silver for medical and research purposes.

In this regard, in vitro approaches have actively been developed in recent years, in which plant extracts are used for the bioreduction of metal ions to form nanoparticles (Harris and Bali, 2008; Ghosh et al., 2012; Rai and Yadav, 2013). These approaches provide a more flexible control over the size and shape of the nanoparticles (for example, by changing the medium pH and reaction temperature), as well as facilitating easy purification. Significantly, this process occurs much faster than the synthesis of nanoparticles in whole plants, because the reaction proceeds almost instantaneously, without the delay required for the uptake and diffusion of metal ions throughout the plant. This in vitro approach has been demonstrated using extracts from a variety of different plant species in combination with a variety of acids and salts of metals, such as copper, gold, silver, platinum, iron, and many others.
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Effect of Silver Nano-Particles on Gray Mold of Tomato Fruits

Effect of Silver Nano-Particles on Gray Mold of Tomato Fruits

When incorporating in a polymer matrix, nanoparticles can enhance the properties of mechanical and barrier, and the act as antimicrobial agent as in the case of Chitosan, with benefits for food quality and safety [7]. Gray mold caused by B. cinerea is the most common crop disease while more than 235 plants have been identified as the host, including legume, strawberry and orchid. Strawberry gray mold is maybe more important diseases, according to the severity of the production [8]. Except B. cinerea, more than fifty plant, fungal pathogens were reported to observe resistance to strobilurin fungicides according to the single-site action mechanism. In Taiwan, also B. cinerea of strawberry had been resistant to azoxystrobin [9]. Some of the studies such as carbon nanotubes, nanoscale silicate platelets, silver nanoparticle and the nanoparticles of TiO2, MgO, ZnO, copper and gold [10].
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Synthesis of plant-mediated silver nano particles using medicinal plant extract and evaluation of its anti microbial activities

Synthesis of plant-mediated silver nano particles using medicinal plant extract and evaluation of its anti microbial activities

The field of nanotechnology is one of the most active areas of research in modern material sciences. Nanotechnology is a field that is developing day by day, making an impact in all spheres of human life (Singh et al., 2010) and creating a growing sense of excitement in the life sciences especially biomedical devices and biotechnology (Prabhu et al., 2010). The use of nanoparticles is gaining impetus in the present century as they posses defined chemical, optical and mechanical properties (Rai et al., 2009 and Gong et al., 2007). Metal nanoparticles are of importance due to their potential applications in catalysis, photonics, biomedicine, antimicrobial activity and optics (Wang et al., 2004; Biswas et al., 2004; Shipway and Willner, 2001; Nie and Emory, 1997; Govindaraju et al., 2008 and Govindaraju et al., 2009). Nanotechnology is expected to open new avenues to fight and prevent disease using atomic scale tailoring of materials. The most promising nanomaterial with antibacterial properties are metallic nanoparticles, which exhibit increased chemical activity due to their large surface to volume ratios and crystallographic surface structure (Parameswari et al., 2010). Metallic nanoparticles are mostly prepared from nobel metals such as Gold, Silver, Platinum and Lead. Among the nobel metals, silver (Ag) is the metal of choice in the field of biological systems, living organisms and medicine (Parashar et al., 2009).
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GOLD NANOPARTICLES IN CANCER THERAPY

GOLD NANOPARTICLES IN CANCER THERAPY

Gold nanoparticles have many properties that are attractive for the use in the cancer therapy. They are small and widely penetrate into the body, preferentially accumulating at the tumor sites owing to EPR effect .They can bind many proteins and drugs and can be actively targeted to cancer cells over expressing cell surface receptors. Gold nanoparticle have high atomic number, which leads to greater absorption of kilovoltage X-rays and provide greater contrasts than standard agents. Gold nanoparticles have been shown to cause radio sensitization at kilovoltage and megavoltage photon energies. The factors that affect gold nanoparticle pharmacokinetics, bio-distribution and in-vivo toxicity need to be clarified. Targeted gold nanoparticle need to exit tumour vasculature, cross the tumour intersitium, enter the cells and potentially exit lysosomes to be effective in-vivo. A standard approach for physicochemical characterization and pre- clinical testing needs to be implemented and this process is being aided by the NLC. With intense global interest in nanotechnology and particularly in nanomedicine.
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A Role of Nano-Science in Drinking Water Refining Systems Deepak Sharma*, Arun Kumar Sharma, Hargyan Singh

A Role of Nano-Science in Drinking Water Refining Systems Deepak Sharma*, Arun Kumar Sharma, Hargyan Singh

Nano-particles are defined as small particles sized between 1 to 100 nanometers in at least one dimension. Currently there are more than 1317 nanotechnology- based consumer products according to an analysis by Nanotechproject.com [1, 5]. Silver nano-particles (AgNPs) are increasingly used in various fields, including medical, food, health care, consumer, and industrial purposes, due to their unique physical and chemical properties. These include optical, electrical, and thermal, high electrical conductivity, and biological properties [1-4]. Due to their peculiar properties, they have been used for several applications, including as antibacterial agents, in industrial, household, and healthcare-related products, in consumer products, medical device coatings, optical sensors, and cosmetics, in the pharmaceutical industry, the food industry, in diagnostics, orthopedics, drug delivery, as anticancer agents, and have ultimately enhanced the tumor-killing effects of anticancer drugs [1]. Recently, AgNPs have been frequently used in many textiles, keyboards, wound dressings, and biomedical devices [2, 5, 6]. Nano sized metallic particles are unique and can considerably change physical, chemical, and biological properties due to their surface-to-volume ratio; therefore, these nano- particles have been exploited for various purposes [7, 8].
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Micro structural parameters of Silver Nano particles using whole pattern fitting technique

Micro structural parameters of Silver Nano particles using whole pattern fitting technique

A typical TEM and SEM micrographs are shown in the Figure 1&Figure 2 respectively of silver nanoaprticles obtained by the synthesis of Parthenium hysterophorus leaf extract. With the help of these micrographs, the average particles size of silver nanoparticles is around 10nm and is cubical in shape. TEM analysis helps us to determine the size of the particles this is due to the fact that during transmission electron microscopy the electrons penetrate through the particle and the beam of electron are analyzed.SEM ananlysis helps us to determine the morphology of the particle since the electrons from the surface are reflected and the beam is of these reflected electrons are scanned. The size value is in accordance with the theoretical value of size of the silver nanoparticles as per XRD analysis.In addition to this the micro structural parameters were refined for individual profiles of X-ray recordings in each of the sample and the computed values of crystallite size <N>, lattice strain (g in %), stacking fault probability and twin fault probability are given in Table 1 for Silver nano particles using exponential distribution function.
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GREEN SYNTHESIS OF SILVER NANOPARTICLES FROM FLOWER EXTRACT OF NERIUM OLEANDER AND ITS CHARACTERIZATION

GREEN SYNTHESIS OF SILVER NANOPARTICLES FROM FLOWER EXTRACT OF NERIUM OLEANDER AND ITS CHARACTERIZATION

There is an increasing commercial demand for nanoparticles due to their wide applicability in various areas such as electronics, catalysis, chemistry, energy, and medicine. This work deals with the synthesis and characterization of silver nanoparticles using Nerium oleander flower. The synthesized nanoparticles were characterized by using UV–Vis absorption spectroscopy, FT-IR and SEM analysis. The reaction mixture turned to brownish gray colour after 5 hrs of incubation and exhibits an absorbance peak around 450 nm

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Determination of silver nanoparticle release from antibacterial fabrics into artificial sweat

Determination of silver nanoparticle release from antibacterial fabrics into artificial sweat

Since the main purpose of fabric samples is to prevent bacteria, the antibacterial effect of the different fabrics was evaluated using S. aureus and E. coli as model Gram- positive and Gram-negative bacteria, respectively. Most of the fabrics used in this study showed a higher antibac- terial activity against S. aureus than that against E. coli (Table 2). The mechanism underlying this antibacterial activity for each of the fabrics was not investigated, but it is likely to not be solely due to nanosilver particles as those fabrics which had silver levels below the detection levels (fabrics B and C) showed essentially as good an antibacterial activity against S. aureus as the silver impregnated fabrics. Perhaps, this then is accounted for by the titanium dioxide. However, the differences between the inhibition of S. aureus and E. coli growth may result from the difference in the compositions of the bacterial cell walls where the cell wall of Gram-negative, but not Gram-positive, bacteria consists of lipopolysac- charides which may provide a more effective protection against bactericides [30]. Certainly, further screening of more representatives of each bacterial division is required to support such a notion.
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Effect on enamel shear bond strength of adding microsilver and nanosilver particles to the primer of an orthodontic adhesive

Effect on enamel shear bond strength of adding microsilver and nanosilver particles to the primer of an orthodontic adhesive

without any statistically relevant impact. The number of teeth with silver spots increased significantly with the addition of silver nanoparticles (particle size 12.6–18.5 nm). Cheng et al. [48] added quaternary ammonium and silver nanoparticles to the primer of Scotchbond Multi-Purpose adhesive. They noted that this primer had esthetics/color similar to those of the control [48]. These authors con- cluded that the high surface area of the silver nanoparti- cles provided a potent effect at a low filler level to avoid negative influence on color and mechanical properties. In a second study, Cheng et al. [49] added silver nano- particles (particle size 2.7 nm) to amorphous calcium phosphate-containing resin. They found that the addition of 0.042% silver nanoparticles imparted no influence on color or flexural strength. Higher concentrations of 0.175% revealed a brownish color and a drop in strength. Therefore, they recommended the addition of only a low concentration of silver nanoparticles. Besinis et al. [50] re- cently applied a silver nanoparticle solution (particle size 56.8 ± 18.6 nm) and a silver nitrate solution (particle size 52.8 ± 18.6 nm) to human dentine discs. Both solutions exhibited an antibacterial effect [50], but only the silver nanoparticle solution achieved a clinically acceptable color match, while the silver nitrate solution produced esthetic- ally unacceptable results [50]. Further studies are needed to investigate whether spots observed in this in vitro study can be removed by cleaning after debonding. If so, the in- corporation of silver particles could be an opportunity to reduce bacterial colonization during orthodontic therapy.
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REVIEW ON GOLD NANO PARTICLE FOR NOVEL DRUG DELIVERY SYSTEM

REVIEW ON GOLD NANO PARTICLE FOR NOVEL DRUG DELIVERY SYSTEM

Some of the most far-reaching consequences of nanotechnology we can foresee are still in the research laboratory. Although the idea of nano-engineered robots circulating our systems like minisubmarines killing diseased cells are fantasy, the ability to make use of and modify biomolecular machines and motors- the proteins and nucleic acids that make life possible is real. For example, recently, a synthetic molecular motor capable of autonomous nanoscale transport inspired by bacterial pathogens was demonstrated. This new biomolecular motor operates by polymerizing a double-helical DNA tail and is hence powered by the free energy of DNA hybridization. Other researchers are using the coded nature of DNA binding to assemble large complex structures, even being able to produce letter shapes which form spontaneously. The exact applications of such work may not be obvious but these are clearly important steps on the path to radical new applications in health care
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Assessment of the Antifungal Effect of Silver Nanoparticles Produced by Pseudomonas sp1 on Screened Fungus in Meymand Historic Village

Assessment of the Antifungal Effect of Silver Nanoparticles Produced by Pseudomonas sp1 on Screened Fungus in Meymand Historic Village

Today, rocky monuments are being exposed to different physical, chemical and biological factors and therefore going to be ruined. One of physical destructive factors is growing of fungus and lichens on the rocks. This research aims to make use of silver nano-particles produced through microbial method in order to prevent growth and progression of fungus detached from rocky surfaces in Meymand historic village. In the first step, some parts of destructed rocky surfaces and grown lichens on rocky monuments in the village were taken as samples and transferred to lab. After isolation of the fungus from the samples, Identification of all samples were done to the genus level by means of conventional mycological methods, morphology on YGC medium and study of microscopic by means of slide culture. Then the effect of silver nano-particles produced by Pseudomonas sp1 on the fungal isolations was studied. Based on what observed, it was proved that nano- particles produced by Pseudomonas sp1 affected about 68.42% on fungal isolations screened from Meymand rocky and historic village and hindered their growth; therefore growth of fungus on historic rocky surfaces can be prevented by means of such particles in order to protect cultural heritages of the society.
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Metal Nano Layer Coating for Improving the Detection and Recognition of Micro Poisons Using Reflection Spectroscopic Measurement

Metal Nano Layer Coating for Improving the Detection and Recognition of Micro Poisons Using Reflection Spectroscopic Measurement

absorption line wavenumber (see Figure 1 right), can indicate the presence of the micro-poison in the aqueous solution if the detected signal is suddenly reduced. The configuration of Figure 1 right can be used for several absorption wavenumbers simultaneously, continuously and real time. In order to compensate the radiation at- tenuation inside the ATR crystal, high power radiation sources can be used. Further increase in sensitivity per- formance can be achieved using metal nano layer coating on the circular ATR configuration shown in Figure 1 right. This can improve significantly the detection and recognition performance of spectroscopic systems due to attraction of organophosphate to the metal nano layer.
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BACTERIAL SYNTHESIS OF SILVER NANOPARTICLES (AGNPS): THE POWERFUL NANOWEAPON

BACTERIAL SYNTHESIS OF SILVER NANOPARTICLES (AGNPS): THE POWERFUL NANOWEAPON

Confirmation of Synthesis of Silver Nanoparticles by FTIR Spectroscopic Analysis The synthesis of AgNPs was further confirmed by FT-IR analysis. The FTIR is a powerful device for identifying types of chemical bonds in a molecule by making an infrared absorption spectrum that is like a molecular "fingerprint" Senapati et al., (2005). [16] The FTIR analytical study was carried out to explore the functional groups and mechanism of AgNPs formation chiefly to identify likely interaction between protein molecules and silver precursor salt leading to the reduction of silver ions and stabilization of AgNPs (Theivasanthi and Alagar, 2013). [17] The characteristic spectrum of silver nanoparticles is shown in Fig. 5 It displays absorption peaks at wavelengths 458, 1335, 1338, 1407, 1456, 1506, 1558, 1635, 1653, 1670 and 3442 cm-1. The absorption peaks nearby 1600 and 1350 cm-1 embodies the presence of NO 2 which may be from silver nitrate solution and the metal precursor associated
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Light Induced Green Synthesis of Silver Nanoparticles Using Aqueous Extract of Prunus amygdalus

Light Induced Green Synthesis of Silver Nanoparticles Using Aqueous Extract of Prunus amygdalus

The most commonly used methods for nano-particle synthesis such as chemical reduction [1], gamma-ray irrad- iation [2], micro-emulsion [3], laser ablation [4], electrochemical reduction [5], autoclaving [6], microwave ir- radiation [7] and photochemical reduction [8] are associated with one or the other disadvantages like toxicity, high operation cost and energy inefficiency, and thus raising many environmental concerns. The quest for envi- ronmental friendly and sustainable methods to synthesize AgNPs has gained momentum during the past decade and shifted the interest of the researchers towards the bio-reduction potential of microorganisms [9]-[12], and plant extracts [13]-[20]. Natural polymers have also been used as reducing and capping agents in the synthesis of nano-particles [21]-[24]. The eco-friendly green synthesis methods suffer from the drawback of longer syn- thesis period for generation of AgNPs [25]. The vital need for efficient and cost effective supplementary me- thods to reduce the reaction time lag has attracted the interest of the researchers on light driven plasmon me- diated reactions [26]. The photon induced methods are gaining increasing interest due to their advantages like controlled reducing action and generation of uniform AgNPs, capability to get absorbed by molecules without any additional absorption promoters and their low cost [27].
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“Green Synthesis, Optimization and Characterization of Silver Nano particles using Aqueous Bark Extract of Casuarina junghuhniana and its Bio Efficacy” by Chathurdevi.G, S. Uma Gowrie, India.

“Green Synthesis, Optimization and Characterization of Silver Nano particles using Aqueous Bark Extract of Casuarina junghuhniana and its Bio Efficacy” by Chathurdevi.G, S. Uma Gowrie, India.

Casuarina junghuhniana Miq. is the most important and widely spread actinorhizal plant due to its uses in soil reclamation, agro- forestry system and as wind breaks. It serves as a rich source of secondary metabolites of potential interest which plays a significant role in regulation of plant communities in growth and resistance to their pests and pathogen. The phytochemicals present in this plant is under explored. Therefore, in our present research work, potential phytochemicals present in aqueous extract of Casuarina junghuhniana bark was assessed and the same was used to synthesize silver nano particles. “Green synthesis” of silver nano particles has gained great interest due to eco-friendly and cost effective. Silver nano particles have wider application in various fields such as medicine, environmental sciences and in industries. In this present work, the silver nano particles were synthesized by the reduction of AgNo 3 using aqueous extract of C.junghuhniana bark. There is a rapid colour change from pale to reddish brown after
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Synthesis of Silver Nanoparticles using Klebs...

Synthesis of Silver Nanoparticles using Klebs...

The antimicrobial effects of sliver ions have been known for long but their activity against microorganisms has not yet been conclusively studied. In the present study, biological synthesis of silver nanoparticles using Klebsiella pneumonia has been investigated. The bacterial strain was grown the appropriate production media. The cell free filtrate obtained on filtration was bought in contact with different concentrations of AgNO 3. . The change in the pH

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A review on biosynthesis of silver nanoparticles and their biocidal properties

A review on biosynthesis of silver nanoparticles and their biocidal properties

Cytotoxicity of nanomaterials depends on their size, shape, coating/capping agent and the type of pathogens against which their toxicity is investigated. Nanoparti- cles synthesized from green method are generally more toxic than those obtained from the non-green method. Some pathogens are more prone to nanomaterials, espe- cially Ag NPs than others due to the presence of both the Ag ions released and Ag NPs. They slowly envelop the microbes and enter into the cell inhibiting their vital functions. It is clear that the fabrication and applica- tion of nanoparticles has resulted in public awareness of their toxicity and impact on the environment [249, 250]. Nanoparticles are relatively more toxic than bulk materials. They are toxic at cellular, subcellular and bio- molecular levels [251]. Oxidative stress and severe lipid peroxidation have been noticed in fish brain tissue on exposure to nanomaterials [252]. The cytotoxicity by Ag NPs is believed to be produced through reactive oxygen species (ROS) as a consequence of which a reduction in glutathione level and an increase in ROS level occur. From in vitro studies on animal tissue and cultured cells, Kim and Ryu [253] have observed an increase in oxida- tive stress, apoptosis and genotoxicity when exposed to silver nanoparticles. Since such studies have been made with varying sizes of Ag NPs and coatings under different
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Tooth Discoloration Induced by Imidazolium Based Silver Nanoparticles as an Intracanal Irrigant

Tooth Discoloration Induced by Imidazolium Based Silver Nanoparticles as an Intracanal Irrigant

imidazolium has been suggested as an intra-canal irri- gant. However, some studies showed that the silver- based materials such as silver-containing sealers (e.g. AH26 and Kerr pulp canal sealer) could make grey to black tooth discoloration. [3, 39-40] The present study aimed to analyse the color changes in enamel and den- tine produced by silver nanoparticle coated with imid- azolium as an irrigant in comparison with NaOCl, CHX, blood (as positive control group), and normal saline (as negative control group).

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