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Green Synthesis of Silver Nanoparticles Using Aqueous Orange and Lemon Peel Extract and Evaluation of Their Antimicrobial Properties
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作者 Amra Bratovcic Amna Dautovic 《Advances in Nanoparticles》 CAS 2024年第2期11-28,共18页
Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the ve... Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the versatility of biomedical applications of metal nanoparticles. In this paper, AgNPs were synthetized at different reaction parameters such as the type and concentration of the extracts, metal salt concentration, temperature, speed stirring, and pH. The antibacterial properties of the obtained silver nanoparticles against E. coli, as well as the physical and chemical characteristics of the synthesized silver nanoparticles, were investigated. UV-Vis spectroscopy was used to confirm the formation of AgNPs. In addition to green biogenic synthesis, chemical synthesis of silver nanoparticles was also carried out. The optimal temperature for extraction was 65˚C, while for the synthesis of AgNPs was 35˚C. The synthesis is carried out in an acidic environment (pH = 4.7 orange and pH = 3.8 lemon), neutral (pH = 7) and alkaline (pH = 10), then for different concentrations of silver nitrate solution (0.5 mM - 1 mM), optimal time duration of the reaction was 60 min and optimal stirring speed rotation was 250 rpm on the magnetic stirrer. The physical properties of the synthesized silver nanoparticles (conductivity, density and refractive index) were also studied, and the passage of laser light through the obtained solution and distilled water was compared. Positive inhibitory effect on the growth of new Escherichia coli colonies have shown AgNPs synthesized at a basic pH value and at a 0.1 mM AgNO<sub>3</sub> using orange or lemon peel extract, while for a 0.5 mM AgNO<sub>3 </sub>using lemon peel extract. 展开更多
关键词 Green Synthesis silver nanoparticles Orange and Lemon Peel Extract Antibacterial Activity Escherichia coli
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Impact Analysis of Microscopic Defect Types on the Macroscopic Crack Propagation in Sintered Silver Nanoparticles
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作者 Zhongqing Zhang Bo Wan +4 位作者 Guicui Fu Yutai Su Zhaoxi Wu Xiangfen Wang Xu Long 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期441-458,共18页
Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,t... Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs. 展开更多
关键词 Sintered silver nanoparticles defect types microscopic defect evolution macroscopic crack propagation molecular dynamics simulation cohesive zone model
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Biosynthesis of Silver Nanoparticles with Clerodendron phlomoides Leave Extract:Particle Morphology,Antimicrobial Potential and Application
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作者 Kirubanandan Shanmugam Subha Veeramani Renganathan Sahadevan 《Journal of Clinical and Nursing Research》 2024年第1期51-64,共14页
Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides... Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications. 展开更多
关键词 silver nanoparticles Clerodendron phlomoides BIOSYNTHESIS Morphology SEM TEM FTIR Antimicrobial activity and wound pathogens
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Root Extracts (<i>Gymnadenia orchidis</i>Lindl) Facilitated Rapid Synthesis of Fluorescent Silver Nanoparticles (Ag-NPs) for Various Biological Applications 被引量:1
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作者 Shilpi Show Chetana Ghosal Brajadulal Chattopadhyay 《Journal of Biomaterials and Nanobiotechnology》 2017年第1期109-124,共16页
One pot rapid and green bio-synthesis of stable fluorescent silver nanoparticles (Ag-NPs) from silver nitrate solution using root extract of Gymnadenia orchidis Lindlat at ambient temperature is demonstrated productiv... One pot rapid and green bio-synthesis of stable fluorescent silver nanoparticles (Ag-NPs) from silver nitrate solution using root extract of Gymnadenia orchidis Lindlat at ambient temperature is demonstrated productively. Surface Plasmon resonance of the synthesized Ag-NPs was shown to occur at 439 nm and two sharp fluorescence peaks at 610 and 780 nm were observed. FTIR study publicized the presence of chemically functional groups in the root extract surrounding the Ag-NPs, acting as stabilizers. XRD and FESEM analysis revealed that Ag-NPs were face centred cubic structure being spherical in shape with an average particle size of 28 ± 2 nm (n = 100). The stability of Ag-NPs in neutral pH environment was confirmed by Zeta Potential (ζ) behaviour. The Ag-NPs showed superior antioxidant activity. The notable photo-catalytic activity of biosynthesized Ag-NPs attributed to the existence of some proteins, responsible for degradation of methylene blue dye. Furthermore, Ag-NPs were found to exhibit a significant antibacterial effect against gram positive Staphylococcus aureus (S. aureus) bacteria. 展开更多
关键词 Green Synthesis Gymnadenia orchidis Lindl silver nanoparticles DPPH Photo-Catalytic Antibacterial
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Antibacterial Chitosan-Gelatin Microcapsules Modified with Green-Synthesized Silver Nanoparticles for Food Packaging 被引量:2
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作者 Long Li Yanan Lu +3 位作者 Yu Chen Jiayi Bian Li Wang Li Li 《Journal of Renewable Materials》 SCIE EI 2023年第1期291-307,共17页
Silver nanoparticles(Ag NPs)are an effective antibacterial agent,but their application in food packaging is limited due to their easy agglomeration and oxidation.In this study,antibacterial microcapsules were fabricat... Silver nanoparticles(Ag NPs)are an effective antibacterial agent,but their application in food packaging is limited due to their easy agglomeration and oxidation.In this study,antibacterial microcapsules were fabricated using Ginkgo biloba essential oil(GBEO)as core material and chitosan and type B gelatin biopolymer as capsule mate-rials.These antibacterial microcapsules were then modified with green-synthesized Ag NPs,blended into the bio-polymer polylactic acid(PLA),and finally formed as films.Physicochemical properties and antibacterial activity against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were evaluated.Results showed that the prepared antibacterial PLA films exhibited excellent antibacterial activity against foodborne pathogens.Its TVC exceeded the limit value of 7 log CFU/g at 7 days compared with the 5 days of pure PLA films.Therefore,these films can extend the shelf life of grass carp fillets by 2–3 days under refrigeration. 展开更多
关键词 silver nanoparticles chitosan GELATIN MICROCAPSULES antibacterial activity food packaging
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The Influence of Tartaric Acid in the Silver Nanoparticle Synthesis Using Response Surface Methodology
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作者 Yatim Lailun Ni’mah Afaf Baktir +1 位作者 Dewi Santosaningsih Suprapto Suprapto 《Journal of Renewable Materials》 EI CAS 2024年第2期245-258,共14页
Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric... Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric acid is an important factor that protects the silver surface and reduces potential cytotoxicity problems.These attributes are critical for assessing the compatibility of AgNPs with biological systems and making them suitable for drug delivery applications.The aim of this research is to conduct a comprehensive study of the effect of tartaric acid concentration,sonication time and temperature on the formation of silver nanoparticles.Using Response Surface Methodology(RSM)with Face-Centered Central Composite Design(FCCD),the optimization process identifies the most favorable synthesis conditions.UV-Vis spectrum regression analysis shows that AgNPs stabilized with tartaric acid are more stable than AgNPs without tartaric acid.This highlights the increased stability that tartaric acid provides in AgNP ssssynthesis.Particle size distribution analysis showed a multimodal distribution for AgNPs with tartaric acid and showed the smallest size peak with an average size of 20.53 nm.The second peak with increasing intensity shows a dominant average size of 108.8 nm accompanied by one standard deviation of 4.225 nm and a zeta potential of−11.08 mV.In contrast,AgNPs synthesized with polyvinylpyrrolidone(PVP)showed a unimodal particle distribution with an average particle size of 81.62 nm and a zeta potential of−2.96 mV.The more negative zeta potential of AgNP-tartaric acid indicates its increased stability.Evaluation of antibacterial activity showed that AgNPs stabilized with tartaric acid showed better performance against E.coli and B.subtilis bacteria compared with AgNPs-PVP.In summary,this study highlights the potential of tartaric acid in AgNP synthesis and suggests an avenue for the development of stable AgNPs with versatile applications. 展开更多
关键词 Tartaric acid silver nanoparticle polyvinyl pyrrolidone response surface methodology
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Improving pressure ulcer care in intensive care units:Evaluating the impact of bundled care and silver nanoparticle dressings
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作者 Hong Yu 《World Journal of Clinical Cases》 SCIE 2024年第19期3873-3881,共9页
BACKGROUND Pressure ulcer(PU)are prevalent among critically ill trauma patients,posing substantial risks.Bundled care strategies and silver nanoparticle dressings offer potential solutions,yet their combined effective... BACKGROUND Pressure ulcer(PU)are prevalent among critically ill trauma patients,posing substantial risks.Bundled care strategies and silver nanoparticle dressings offer potential solutions,yet their combined effectiveness and impact on patient satisfaction remain insufficiently investigated.AIM To assess the impact of bundled care along with silver nanoparticle dressing on PUs management and family satisfaction in critically ill trauma patients.METHODS A total of 98 critically ill trauma patients with PUs in intensive care unit(ICU)were included in this study.Patients were randomly assigned to either the control group(conventional care with silver nanoparticle dressing,n=49)or the intervention group(bundled care with silver nanoparticle dressing,n=49).The PU Scale for Healing(PUSH)tool was used to monitor changes in status of pressure injuries over time.Assessments were conducted at various time points:Baseline(day 0)and subsequent assessments on day 3,day 6,day 9,and day 12.Family satisfaction was assessed using the Family Satisfaction ICU 24 ques-tionnaire.RESULTS No significant differences in baseline characteristics were observed between the two groups.In the intervention group,there were significant reductions in total PUSH scores over the assessment period.Specifically,surface area,exudate,and tissue type parameters all showed significant improvements compared to the control group.Family satisfaction with care and decision-making was notably higher in the intervention group.Overall family satisfaction was significantly better in the intervention group.CONCLUSION Bundled care in combination with silver nanoparticle dressings effectively alleviated PUs and enhances family satisfaction in critically ill trauma patients.This approach holds promise for improving PUs management in the ICU,benefiting both patients and their families. 展开更多
关键词 Pressure ulcers silver nanoparticle dressings Bundled care Pressure ulcer scale for healing tool Family satisfaction
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Molluscicidal effect of green synthesized silver nanoparticles using Azadirachta indica on Biomphalaria alexandrina snails and Schistosoma mansoni cercariae
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作者 Salwa S.Younis Iman F.Abou-El-Naga Khaled H.Radwan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第1期35-44,共10页
Objective:To assess the molluscicidal effect of the eco-friendly green synthesized neem silver nanoparticles(neem-Ag NPs)against Biomphalaria alexandrina,the snail intermediate host for Schistosoma mansoni,and their c... Objective:To assess the molluscicidal effect of the eco-friendly green synthesized neem silver nanoparticles(neem-Ag NPs)against Biomphalaria alexandrina,the snail intermediate host for Schistosoma mansoni,and their cercaricidal potential.Methods:Methanol extracts from neem fruits were used for green synthesis of neem-Ag NPs.The neem-Ag NPs were characterized using UV-visible absorption spectra,dynamic laser light scattering technique,and transmission electron microscopy.The potential molluscicidal effect against adult and juvenile Biomphalaria alexandrina and the effect of the sub-lethal concentration on hatching of snail eggs and Schistosoma mansoni cercariae were evaluated.Results:The surface plasmon resonance of neem-Ag NPs showed a sharp absorption peak atλ_(max)=518 nm together with multiple peaks.The hydrodynamic diameter was(77.15±34.53)nm,the polydispersity index(0.338±0.000)and the zeta-potential-14.07 mV.Moreover,transmission electron microscopy showed that the average size of the nanoparticles was(27±2)nm.Agglomeration was evident and a light-colored capping layer could be seen coating the nanoparticles.Juvenile snails(LC_(50):0.83 ppm)were more susceptible to neem-Ag NPs than adults(LC_(50):1.07 ppm).In addition,neem-Ag NPs and neem at LC_(50)concentrations inhibited the egg-hatching of snails and showed cercaricidal activity in a time-dependent manner.Conclusions:Neem-Ag NPs have lethal activities against Biomphalaria alexandrina snails and their eggs,as well as Schistosoma mansoni cercariae.Hence,neem-Ag NPs could be a potential agent to control schistosomiasis. 展开更多
关键词 Biomphalaria alexandrina NEEM Schistosoma mansoni Azadirachta indica silver nanoparticles MOLLUSCICIDE
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Toxicity and Molecular Mechanisms of Actions of Silver Nanoparticles
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作者 Gemechis Waktole 《Journal of Biomaterials and Nanobiotechnology》 2023年第3期53-70,共18页
Silver nanoparticles (AgNPs) have gained popularity due to their antibacterial properties, and are therefore widely used in several applications such as wound dressings, food packaging, and water purification. However... Silver nanoparticles (AgNPs) have gained popularity due to their antibacterial properties, and are therefore widely used in several applications such as wound dressings, food packaging, and water purification. However, the toxicity of AgNPs to humans and the environment is a growing concern. This review aims to summarize the current knowledge on the toxicity and molecular mechanisms of action of AgNPs. The toxicity of AgNPs can be attributed to their small size, which allows them to enter cells and interact with cellular components. Reports suggest that AgNPs can induce cell death, DNA damage, and oxidative stress in various cell types. The toxic effects of AgNPs differ based on their size, shape, surface charge, and coating. The molecular mechanisms behind the toxicity of AgNPs involve the production of reactive oxygen species, disruption of cellular membranes, and activation of proinflammatory cytokines. Overall, the toxicity of AgNPs is dependent on various factors, and more research is needed to fully understand the mechanisms behind their toxicity. This review highlights the need for proper risk assessments and regulations to minimize the adverse effects of AgNPs on human health and the environment. 展开更多
关键词 TOXICITY silver nanoparticles Molecular Mechanisms
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Performance of Rhodamine-Sensitized Solar Cells Fabricated with Silver Nanoparticles
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作者 Bandana Ranamagar Isaac Abiye +2 位作者 Himsheela Karki Yucheng Lan Fasil Abebe 《Advances in Nanoparticles》 CAS 2023年第2期68-79,共12页
A plasmonic effect of silver nanoparticles (AgNPs) in dye-sensitized solar cells (DSSCs) is studied. In this investigation, the efficiency of dye-sensitized solar cells has been remarkably increased by infusion of syn... A plasmonic effect of silver nanoparticles (AgNPs) in dye-sensitized solar cells (DSSCs) is studied. In this investigation, the efficiency of dye-sensitized solar cells has been remarkably increased by infusion of synthesized silver nanoparticles into the TiO<sub>2</sub> photoanode. Rhodaminederivative RdS1 was synthesized by microwave-assisted condensation of hydrazide and 3-for-mylchromone. The synthesized silver nanoparticles were characterized with UV/Vis absorption spectroscopy and transmission electron microscopy. The interfacial charge transport phenomena of the dye-sensitized solar cell (DSSCs) are determined by electrochemical impedance spectroscopy and the corresponding efficiencies are calculated using current-voltage (I-V) curve. The solar cell photoanode with silver nanoparticles infused with RdS1 in titanium dioxide had the highest solar-to-electric power efficiency at 0.17%. 展开更多
关键词 TiO2 silver nanoparticles RHODAMINE Optical Dye-Sensitized Solar Cell
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mRNA transcriptome profiling of human hepatocellular carcinoma cells HepG2 treated with Catharanthus roseus-silver nanoparticles
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作者 Nur Asna Azhar Siti Aishah Abu Bakar +1 位作者 Marimuthu Citartan Nor Hazwani Ahmad 《World Journal of Hepatology》 2023年第3期393-409,共17页
BACKGROUND The demand for the development of cancer nanomedicine has increased due to its great therapeutic value that can overcome the limitations of conventional cancer therapy.However,the presence of various bioact... BACKGROUND The demand for the development of cancer nanomedicine has increased due to its great therapeutic value that can overcome the limitations of conventional cancer therapy.However,the presence of various bioactive compounds in crude plant extracts used for the synthesis of silver nanoparticles(AgNPs)makes its precise mechanisms of action unclear.AIM To assessed the mRNA transcriptome profiling of human HepG2 cells exposed to Catharanthus roseus G.Don(C.roseus)-AgNPs.METHODS The proliferative activity of hepatocellular carcinoma(HepG2)and normal human liver(THLE3)cells treated with C.roseusAgNPs were measured using MTT assay.The RNA samples were extracted and sequenced using BGIseq500 platform.This is followed by data filtering,mapping,gene expression analysis,differentially expression genes analysis,Gene Ontology analysis,and pathway analysis.RESULTS The mean IC 50 values of C.roseusAgNPs on HepG2 was 4.38±1.59μg/mL while on THLE3 cells was 800±1.55μg/mL.Transcriptome profiling revealed an alteration of 296 genes.C.roseusAgNPs induced the expression of stress-associated genes such as MT,HSP and HMOX-1.Cellular signalling pathways were potentially activated through MAPK,TNF and TGF pathways that are responsible for apoptosis and cell cycle arrest.The alteration of ARF6,EHD2,FGFR3,RhoA,EEA1,VPS28,VPS25,and TSG101 indicated the uptake of C.roseus-AgNPs via both clathrin-dependent and clathrinindependent endocytosis.CONCLUSION This study provides new insights into gene expression study of biosynthesised AgNPs on cancer cells.The cytotoxicity effect is mediated by the aberrant gene alteration,and more interestingly the unique selective antiproliferative properties indicate the C.roseusAgNPs as an ideal anticancer candidate. 展开更多
关键词 Catharanthus roseus HEPG2 silver nanoparticles TRANSCRIPTOME oxidative stress Apoptosis Cell cycle
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Green Synthesis and Antibacterial Properties of Silver Nanoparticles from Eugenia uniflora Fruit Extract
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作者 Melissa Moya Vanessa Bagnarello +1 位作者 Julio Mora Idalia Valerio 《Advances in Nanoparticles》 2023年第3期94-105,共12页
The synthesis of nanoparticles by biological methods using microorganisms, enzymes, or plant extracts has been suggested as a possible ecofriendly alternative to chemical and physical methods that involve the use of h... The synthesis of nanoparticles by biological methods using microorganisms, enzymes, or plant extracts has been suggested as a possible ecofriendly alternative to chemical and physical methods that involve the use of harmful reducing agents. Green synthesis of silver nanoparticles (AgNPs) was achieved using Eugenia uniflora ripe fruit extract, which was characterized by phytochemical screening revealing the presence of polyphenols (quinones, flavonoids, and tannins), reducing compounds, and terpenes. These excellent antioxidants reduced silver nitrate to give the AgNPs, which were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), and ζ potential analysis. The diameter of the AgNPs ranged from 10.56 ± 1.2 nm to 107.56 ± 5.7 nm. The antibacterial activity of the AgNPs was evaluated using a modification of the Kirby-Bauer technique with Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The inhibition halos were 11.12 ± 0.02 mm, 13.96 ± 0.07 mm, and 11.29 ± 0.76 mm, respectively. The synthesis using E. uniflora is an ecofriendly and low cost method of obtaining silver nanoparticles that could be used in health sciences because of their activity against bacteria with antibiotic resistance. 展开更多
关键词 Eugenia uniflora Green Synthesis silver nanoparticles Antibacterial Activity POLYPHENOLS
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Biosynthesis and Characterization of Silver Nanoparticles Coated with Metabolites Extracted from Clerodendron phlomoides with Its Biochemical Studies in Liver Tissue
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作者 Subha Veeramani Kirubanandan Shanmugam 《Proceedings of Anticancer Research》 2023年第4期1-19,共19页
Silver nanoparticles(AgNPs)have been used as a potential nanomaterial-based drug delivery vehicle for liver cancer treatment,as it induces cell death and produces cytotoxicity against cancerous cells at a low concentr... Silver nanoparticles(AgNPs)have been used as a potential nanomaterial-based drug delivery vehicle for liver cancer treatment,as it induces cell death and produces cytotoxicity against cancerous cells at a low concentration.The biosynthesis of green metallic nanoparticles uses secondary metabolites in plant extracts instead of toxic chemicals for a reduction-oxidation(redox)reaction.The biosynthesis of AgNPs with the aqueous extract of Clerodendron phlomoides was performed in this study.The phytochemical analysis of C.phlomoides extract using gas chromatography-mass spectrometry(GC-MS)confirmed the presence of redox metabolites.The peak at 489 nm in UV-visible spectra confirmed the formation of bioactive AgNPs reduced from silver nitrate solution,whereas the Fourier-transform infrared(FTIR)spectra indicated the bioactive molecules of plant extracts that are responsible for the formation.Scanning electron microscope(SEM)micrograph revealed the formation of spherical and ovoid structures of AgNPs,whereas transmission electron microscope(TEM)micrograph confirmed the size of AgNPs,which varies from 25 nm to 100 nm.X-ray diffraction(XRD)spectra showed the crystalline nature of AgNPs,and the size of crystallite was 4 nm,while dynamic light scattering(DLS)analysis confirmed the average particle size of AgNPs to be around 125 nm.In vivo studies showed that bioactive AgNPs have a significant anticancer potential against liver cancer,whereas biochemical studies of rats’liver tissue samples confirmed that bioactive AgNPs produced a potential hepatoprotective effect against diethylnitrosamine-induced liver cancer. 展开更多
关键词 silver nanoparticles Clerodendron phlomoides Aqueous extract SEM TEM Liver cancer
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Hydrothermal synthesis of silver nanoparticles in Arabic gum aqueous solutions 被引量:2
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作者 黎应芬 甘卫平 +3 位作者 周健 鲁志强 杨超 戈田田 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期2081-2086,共6页
Finely divided silver nanoparticles were synthesized via the hydrothermal method. Arabic gum (AG) was used as both the reductant and steric stabilizer without any other surfactant. By adjusting the reaction temperat... Finely divided silver nanoparticles were synthesized via the hydrothermal method. Arabic gum (AG) was used as both the reductant and steric stabilizer without any other surfactant. By adjusting the reaction temperature, mass ratio of AG to AgNO3, and reaction time, silver nanoparticles with different morphological characteristics could be obtained. The products were characterized by UV-Vis, FTIR, TEM, SEM, and XRD measurements. It was found that temperature and AG played an important role in the synthesis of mono-disperse silver nanoparticles. Well dispersed and quasispherical silver nanoparticles were obtained under the optimal synthesis conditions of 10 mmol/L AgNO3, m(AG)/m(AgN03)= l:1, 160 ℃ and 3 h. 展开更多
关键词 silver nanoparticles hydrothermal method Arabic gum green chemistry
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Synthesis of silver nanoparticles using leaves of Catharanthus roseus Linn.G.Don and their antiplasmodial activities 被引量:9
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作者 Ponarulselvam S Panneerselvam C +3 位作者 Murugan K Aarthi N Kalimuthu K Thangamani S 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期574-580,共7页
Objective:To develop a novel approach for the green synthesis of silver nanoparticles using aqueous leaves extracts of Catharanthus roseus(C.roseus) Linn.G.Don which has been proven aclive against malaria parasite Pla... Objective:To develop a novel approach for the green synthesis of silver nanoparticles using aqueous leaves extracts of Catharanthus roseus(C.roseus) Linn.G.Don which has been proven aclive against malaria parasite Plasmodium falciparum(P.falciparum).Methods:Characterizations were determined by using ultraviolet-visible(UV-Vis) spectrophotometry,scanning electron microscopy(SEM).energy dispersive X-ray and X-ray diffraction.Results:SLM showed the formation of silver nanoparticles with an average size of 35-55 nm.X-ray diffraction analysts showed that the particles were crystalline in nature with face centred cubic structure of the hulk silver with the broad peaks at 32.4.46.4 and 28.0.Conclusions:It can be concluded that the leaves of C.roseus can he good source for synthesis of silver nanoparticle which shows aiitiplasmodial activity against P.falciparum.The important outcome of the study will he the development of value added products from medicinal plants C.roseus lor hionicdical and nanotechnology based industries. 展开更多
关键词 silver nanoparticles CATHARANTHUS roseus PLASMODIUM FALCIPARUM ANTIPLASMODIAL activity
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Antibacterial Characterization of Silver Nanoparticles against E.Coli ATCC-15224 被引量:10
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作者 M.Raffi F.Hussain +3 位作者 T.M.Bhatti J.I.Akhter A.Hameed M.M.Hasan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第2期192-196,共5页
Silver nanoparticles of mean size 16 nm were synthesized by inert gas condensation (IGC) method. Crystalline structure, morphology and nanoparticles size estimation were conducted by X-ray diffraction (XRD) and tr... Silver nanoparticles of mean size 16 nm were synthesized by inert gas condensation (IGC) method. Crystalline structure, morphology and nanoparticles size estimation were conducted by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Antibacterial activity of these silver nanoparticles as a function of particles concentration against gram-negative bacterium Escherichia coli (E. coli) was carried out in liquid as well as solid growth media. Scanning electron microscopy (SEM) and TEM studies showed that silver nanoparticles after interaction with E.coli have adhered to and penetrated into the bacterial cells. Antibacterial properties of silver nanoparticles are attributed to their total surface area, as a larger surface to volume ratio of nanoparticles provides more efficient means for enhanced antibacterial activity. 展开更多
关键词 silver nanoparticles ANTIBACTERIAL Electron microscopy
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Rapid Preparation Process of Silver Nanoparticles by Bioreduction and Their Characterizations 被引量:13
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作者 傅谋兴 李清彪 +5 位作者 孙道华 卢英华 何宁 邓旭 王惠璇 黄加乐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第1期114-117,共4页
Bioreduction as a novel nanoparticle synthesizing technology attracts increasing attention. Dried cells of the bacterium Aeromonas sp. SH10 rapidly reduced [Ag(NH3)2]^+ to Ago in the solution into which some amount... Bioreduction as a novel nanoparticle synthesizing technology attracts increasing attention. Dried cells of the bacterium Aeromonas sp. SH10 rapidly reduced [Ag(NH3)2]^+ to Ago in the solution into which some amount of OH^- was introduced. The surface plasmon resonance centered at 425 nm on the UV-vis spectra and five broad Bragg reflections on the XRD pattern showed that stable silver nanoparticles were formed during the bioreduction process. TEM and SEM observations suggested that the silver nanoparticles were uniform in size and well dispersed on the cells and in the solution. Therefore, silver nanoparticles could be prepared rapidly by this bioreduction technology. 展开更多
关键词 BIOREDUCTION silver nanoparticlE BACTERIUM HYDROXIDE
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Biogenesis of antibacterial silver nanoparticles using the endophytic bacterium Bacillus cereus isolated from Garcinia xanthochymus 被引量:5
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作者 Swetha Sunkar C Valli Nachiyar 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第12期953-959,共7页
Objective:To synthesize the ecofriendly nanoparticles,which is viewed as an alternative to the chemical method which initiated the use of microbes like bacteria and fungi in their synthesis.Methods:The current study u... Objective:To synthesize the ecofriendly nanoparticles,which is viewed as an alternative to the chemical method which initiated the use of microbes like bacteria and fungi in their synthesis.Methods:The current study uses the endophytic bacterium Bacillus cereus isolated from the Garcinia xanthochymus to synthesize the silver nanoparticles(AgNPs).The AgNPs were synthesized by reduction of silver nitrate solution by the endophytic bacterium after incubation for 3-5 d at room temperature.The synthesis was initially observed by colour change from pale white to brown which was confirmed by UV-Vis spectroscopy.The AgNPs were further characterized using FTIR,SEM-EDX and TEM analyses.Results:The synthesized nanoparticles were found to he spherical with the size in the range of 20-40 nm which showed a slight aggregation.The energy-dispersive spectra of the nanoparticle dispersion confirmed the presence of elemental silver.The AgNPs were found to have antibacterial activity against a few pathogenic bacteria like Escherichia coli,Pseudomonas aeruginosa,Staphylococcus aureus,Salmonella typhi and Klebsiella pneumoniae.Conclusions:The endophytic bacteria identified as Bacillus cereus was able to synthesize silver nanoparticles with potential antibacterial activity. 展开更多
关键词 ENDOPHYTIC bacteria Bacillus CEREUS silver nanoparticles UV-Vis spectra SEM TEM ANTIBACTERIAL activity
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Catharanthus roseus:a natural source for the synthesis of silver nanoparticles 被引量:4
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作者 Mukunthan KS Elumalai EK +1 位作者 Trupti N Patel V Ramachandra Murty 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第4期270-274,共5页
Objective:To develop a simple rapid procedure for bioreduction of silver nanoparticles(AgNPs)using aqueous leaves extracts of Catharanthus roseus(C.roseus).Methods:Characterization were determined by using UV-Vis spec... Objective:To develop a simple rapid procedure for bioreduction of silver nanoparticles(AgNPs)using aqueous leaves extracts of Catharanthus roseus(C.roseus).Methods:Characterization were determined by using UV-Vis spectrophotometry,scanning electron microscopy(SEM),energy dispersive X-ray and X-ray diffraction.Results:SEM showed the formation of silver nanoparticles with an average size of 67 nm to 48 nm.X-ray diffraction analysis showed that the particles were crystalline in nature with face centered cubic geometry.Conclusions:C.roseus demonstrates strong potential for synthesis of silver nanoparticles by rapid reduction of silver ions(Ag^+ to Ag^0).This study provides evidence for developing large scale commercial production of value-added products for biomedical/nanotechnology-based industries. 展开更多
关键词 nanoparticles NANOTECHNOLOGY silver CATHARANTHUS roseus
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EFFECTS OF DIFFERENT FUNCTIONAL GROUP-CONTAINING ORGANICS ON MORPHOLOGY-CONTROLLED SYNTHESIS OF SILVER NANOPARTICLES AT ROOM TEMPERATURE 被引量:5
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作者 A.L. Wang H.B. Yin +3 位作者 M. Ren X.N. Cheng Q.F. Zhou X.F. Zhang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2006年第5期362-370,共9页
Silver nanoparticles with average particles sizes ranging from 2 to 131nm were manipulatively synthesized starting from silver nitrate using different functional group-containing organic modifiers at room temperature.... Silver nanoparticles with average particles sizes ranging from 2 to 131nm were manipulatively synthesized starting from silver nitrate using different functional group-containing organic modifiers at room temperature. The effects of the organic modifiers on the morphology of the resulting silver nanoparticles were strongly dependent on the intrinsic properties of the functional groups and the reducibility of the reductant. Numerous ether bonds (-0-)present in polyethylene glycol and Tween-80 were beneficial to the formation of silver nanoparticles with particle sizes of several nanometers in a narrow size distribution in both weak and strong reducing environments. Cetyltrimethylammonium bromide induced the formation of nanosized silver triangle plates in a weak reducing environment. The crystal growth of the silver nanoparticles with particle sizes of more than lOnm was postulated through an adhesion process of small-sized particles followed by a subsequent coalescence process under the present reaction conditions. 展开更多
关键词 silver nanoparticle NANOSTRUCTURE crystal growth TEM (transmissionelectron microscopy)
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