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Facile synthesis of aqueous silver nanoparticles and silver/molybdenum disulfide nanocomposites and investigation of their nonlinear optical properties

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Tungsten 2021年第4期3卷 482-491页

作者： Xiao-Yan Zhang Hong-Qiang Wang Yi Sun Wei Zhou Jun Wang Department of Chemistry Shanghai UniversityShanghai 200444China Laboratory of Micro-Nano Photonic and Optoelectronic Materials and Devices Key Laboratory of Materials for High-Power LaserShanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China Center of Materials Science and Optoelectronic Engineering University of Chinese Academy of SciencesBeijing 100049China Shanghai Aerospace Hydrogen Energy Technology Co. LtdShanghai 201108China State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China

silver nanoparticle (AgNP) aqueous colloids with different surface plasmon resonance (SPR) frequencies were controllably synthesized by a facile and green chemical synthesis method. The obtained AgNPs with an average diameter of ~ 15 nm show a symmetrical SPR peak at ~ 400 nm. Another longitudinal SPR mode at ~ 520 nm occurs when increasing the amount of ethanol according to the ultraviolet-visible light spectra. The third-order nonlinear optical (NLO) absorption properties of the AgNP colloids were found to switch from two-photon absorption (TPA) to saturable absorption (SA) by tuning the SPR frequency using Z-scan technique with 340 fs pulses at 515 nm. When combined with two-dimensional (2D) MoS_(2), an enhanced SA response is observed for Ag/MoS_(2 )nanocomposites compared with the counterparts. The nonlinear absorption coefficient of Ag/MoS_(2) nanocomposites is about − (10.93 ± 0.6) × 10^(-2 )cm·GW^(−1), which is almost three times higher than that of MoS_(2). Our work has an instructive value in promoting the potential application of AgNPs and its nanocomposites in optoelectronic and photonic devices, such as optical limiting and ultrafast laser pulse generation.

关键词： silver nanoparticles Two-dimensional molybdenum disulfide Chemical synthesis Nonlinear effects Optical properties

Green synthesis of silver nanoparticles using aqueous extract of saffron(Crocus sativus L.) wastages and its antibacterial activity against six bacteria

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Asian Pacific Journal of Tropical Biomedicine 2017年第3期7卷 227-233页

作者： Ghodsieh Bagherzade Maryam Manzari Tavakoli Mohmmad Hasan Namaei Department of Chemistry College of ScienceUniversity of BirjandBirjand 97179-414Iran Hepatitis Research Center Birjand University of Medical SciencesBirjand 97179-414Iran

Objective: To synthesis silver nanoparticles(Ag NPs) by using extract of saffron(Crocus sativus L.) wastages and to test their antibacterial activity against six ***: In this paper, the synthesis of Ag NPs using aqueous extract of saffron wastage as a green method without any chemical stabilizer and reducer is demonstrated. The synthesized Ag NPs were determined by UV–vis spectrum, high resolution transmission electron microscopy, X-ray diffraction, and Fourier transmission infrared spectroscopy ***: UV–vis spectrum showed a peak at 450 nm due to excitation of surface plasmon vibrations. Fourier transmission infrared spectroscopy showed that nanoparticles were capped with plant secondary metabolites. X-ray diffraction analysis also demonstrated that the size range of the synthesized nanoparticles was 12–20 nm. Transmission electron microscope image illustrated Ag NPs with spherical shape and an average size of15 nm. The result of antibacterial activities showed that the biosynthesized Ag NPs had an inhibiting activity against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Shigella flexneri and Bacillus ***: The biosynthesized Ag NPs showed significant antibacterial effect against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Shigella flexneri and Bacillus subtilis, so, it can be used in biomedical applications.

关键词： nanoparticles Antibacterial activities silver nanoparticles Saffron wastage Inhibiting activity

Biochar amendment changed soil-bound fractions of silver nanoparticles and ions but not their uptake by radish at an environmentally-relevant concentration

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Biochar 2020年第3期2卷 307-317页

作者： Jianzhou He Yuanbo Li Haonan Qi Hui Li Wei Zhang Department of Plant Soil and Microbial SciencesMichigan State UniversityEast LansingMI 48824USA Institute of Plant Protection Chinese Academy of Agricultural SciencesBeijing 100193China Institute for Integrative Toxicology Michigan State UniversityEast LansingMI 48824USA Environmental Science and Policy Program Michigan State UniversityEast LansingMI 48824USA

Plant uptake of silver nanoparticles(Ag NPs)and ions(Ag^(+))largely depends on their exchangeable and soil-bound fractions in soils,which may be influenced by biochar *** study investigated the effects of biochar amendment(0.1%and 1.0%)on soil sorption of Ag NPs and Ag^(+),their soil-bound fractions,and their uptake and translocation by radish grown in a loamy sand soil spiked with 1 mg/kg Ag NPs or Ag^(+).Sorption of Ag^(+)to the soils was much greater than that of Ag NPs,mainly because negatively charged soil particles would attract Ag^(+),but repel negatively charged Ag *** amend-ment at 1.0%(by weight)significantly decreased the reducible fraction of Ag^(+)in the soils with and without radish plants and increased the oxidisable fraction of Ag NPs in the soils with radish *** amendment had no significant effect on Ag uptake by radish plants(p>0.05),probably due to low exchangeable Ag fractions in all experimental *** this short-term experiment(35 days),the addition of 1 mg/kg Ag NPs or Ag^(+)did not substantially elevate the level of Ag in radish roots(0.05±0.02-1.06±0.98 mg/kg)and shoots(0.01±0.00-0.03±0.01 mg/kg),compared to the blank control(p>0.05).Radish uptake of Ag NPs and Ag^(+)at the environmentally-relevant concentration was low with root concentration factors between 0.03±0.03 to 0.29±0.21 and root-to-shoot translocation factors between 0.08±0.10 to 0.89±1.21,which may partially explain the non-significant effect of biochar amendment on Ag uptake.

关键词： silver nanoparticles Biochar Fractionation Uptake Radish

Preparation and properties of cellulose nanocomposite fabrics with in situ generated silver nanoparticles by bioreduction method

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Journal of Bioresources and Bioproducts 2021年第1期6卷 75-81页

作者： Battu Deeksha Vajja Sadanand NHariram Anumakonda Varada Rajulu Department of Chemical Engineering Osmania UniversityHyderabad500007India Department of Chemistry Osmania UniversityHyderabad500007India Department of Biochemistry Kalasalingam UniversityAnand NagarKrishnankovil626126India Centre for Composite Materials International Research CentreKalasalingam UniversityAnand NagarKrishnankovil 626126India

The aim of the present study was to develop antibacterial cellulose(cotton)nanocomposite fab-rics(CNCFs)with in situ generated silver nanoparticles using medicinal plant Vitex leaf *** developed CNCFs were characterized by scanning electron microscope(SEM),Fourier transform infrared(FT-IR)spectroscopy,X-ray diffraction(XRD)and antibacterial ***,these CNCFs possessed good antibacterial *** CNCFs prepared using simple and environmentally friendly method can be considered for medical applications in,such as,surgical aprons,wound cleaning,wound dressing,and hospital bed materials.

关键词： Cotton fabrics silver nanoparticles In situ generation Antibacterial activity

Physicochemical properties and antibacterial application of silver nanoparticles stabilized by whey protein isolate

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Food Bioscience 2022年第2期46卷 498-506页

作者： Aoqiong Zeng Beibei Wang Cheng Zhang Ruijin Yang Shuhuai Yu Wei Zhao State Key Laboratory of Food Science and Technology School of Food Science and TechnologyJiangnan University1800 Lihu AvenueWuxiJiangsu214122PR China National Engineering Research Center for Functional Food Jiangnan University1800 Lihu AvenueWuxiJiangsu214122PR China

Nano metal materials have been widely explored to be applied in medical,environmental,and material *** these nanoparticles,especially silver nanoparticles(AgNPs),have drawn increasing attention for antimicrobial *** researchers are keen on the development of the biologically friendly capping reagents for the synthesis of AgNPs,instead of unfriendly organic *** this study,the liquid chemical reduction method was used to synthesize AgNPs with edible whey protein isolate(WPI)as a capping *** WPI-AgNPs had a broad size distribution(average diameter of 138.6 nm),and their dimensions could be readily controlled in the range of 22.5-149.6 nm by introducing different concentrations of ***,it was confirmed that WPI-AgNPs were formed through two mechanisms,which were respectively reduced in situ(without the addition of NaCl)and ex situ(in presence of NaCl)to yield silver *** WPI-AgNPs synthesized in presence of 10 mM of NaCl as mediation reagent were stable at room temperature or 4℃ up to 3 ***,the synthesized WPI-AgNPs had a good antibacterial activity toward pathogens including Gram-negative *** and Gram-positive *** results shed light on method and capping reagent to stabilize silver nanoparticles,which highlighted the potential of WPI and chloride in metal nanoparticle synthesis.

关键词： silver nanoparticles Whey protein isolate Chloride Liquid chemical reduction method

Polyvinylpyrrolidone as an Efficient Stabilizer for silver nanoparticles

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Chinese Journal of Chemistry 2014年第9期32卷 909-913页

作者： Weidong Huang Linxia Zhang Qiuping Yang Zhimin Wang School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China

Aggregation of nanoparticles is a serious problem in their *** this article,stability of biosynthesized silver nanoparticles(AgNPs)was initially studied with different concentrations of sodium chloride(NaCl).Surfactant screening showed that polyvinylpyrrolidone(PVP)was an ideal stabilizer,which not only was effective at a low concentration(0.1%,V/V),but also could protect silver colloids from aggregation for a long period at 1 mol•L^(−1) NaCl,and 6 h even at 3 mol•L^(−1) ***,some other surfactants,such as sodium dodecyl(SDS),Triton X-100,Tween-20,and Tween-80,could not prevent AgNPs from aggregation even at a high concentration up to 0.5%(V/V).This AgNPs stabilizer is simple and convenient for a variety of applications compared with others.

关键词： silver nanoparticles polyvinylpyrrolidone stabilizer NaCl

Antiplasmodial activity of silver nanoparticles: A novel green synthesis approach

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Asian Pacific Journal of Tropical Biomedicine 2018年第5期8卷 268-272页

作者： Madhur Sardana Varnika Agarwal Akansha Pant Vinita Kapoor Kailash C.Pandey Sanjay Kumar Department of Chemistry Sri Venkateswara College University of Delhi National Institute of Malaria Research ICMR Department of Biochemistry National Institute for Research in Environmental HealthICMR

Objective:To synthesize silver nanoparticles using silver nitrate by a green technique which involves different compositions of aqueous leaf extracts of Azadirachta indica(neem)and Ocimum sanctum(tulsi).Methods:Their shape and size were determined using transmission electron microscopy and UV-visible *** antiplasmodial activity was studied using the malarial parasite strain(Plasmodium falciparum,3D7).The parasite strain(3D7)was collected and revived in vitro using Trager and Jensen method in RPMI 1640 medium for *** maximal effective concentration values were calculated by nonlinear regression ***:Transmission electron microscopy results confirmed the formation of silver nanoparticles with size ranging from 4.74-39.32 nm and their size differs by varying the concentrations from 20%to 100%of neem extract in neem and tulsi *** was observed that samples B and C showed half maximum effective concentration of about 0.3μ***:It can be easily established that the aqueous leaf extracts of neem and tulsi in combination can be a good source for synthesis of silver nanoparticles with small size possessing appreciable antiplasmodial activity.

关键词： Malaria Antiplasmodial activity silver nanoparticles Green synthesis Azadirachta indica Ocimum sanctum

Biological activities of silver nanoparticles from Nothapodytes nimmoniana(Graham)*** extracts

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Food Science and Human Wellness 2016年第4期5卷 207-218页

作者： G.Mahendran B.D.Ranjitha Kumari Department of Plant Science School of Life SciencesBharathidasan UniversityTiruchirappalli620024 Tamil NaduIndia

In the present investigation,we have described the green biosynthesis of silver nanoparticles(AgNPs)using ripened fruit aqueous extract of Nothapodytes nimmoniana(Graham)*** capping *** antioxidant,anticancer and antimicrobial activities of AgNPs were also *** analysis revealed that AgNPs had a sharp peak at 416 nm.X-ray diffraction(XRD)result confirmed the characteristic peaks indicated at 111,200,220 and 311 for the crystalline of the face centered cubic *** Scanning Electron Microscopy analysis results confirmed the spherical shaped of AgNPs with difference sizes of the particles and an average from 44 to 64 ***,fruit extract and AgNPs were evaluated total phenolic,tannin and flavonoid contents and were subjected to assess their antioxidant potential using various in vitro systems such as using 1,1-diphenyl-2-picryl-hydrazyl(DPPH),2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS),metal chelating,phosphomolybdenum and ferric reducing antioxidant power(FRAP)activities and antimicrobial activity against Bacillus subtilis,Pseudomonas aeruginosa,Klebsiella pneumoniae,Staphylococcus aureus and Escherichia *** compared to AgNPs,fruit extract exhibited uppermost radical scavenging *** addition,the cytotoxicity activity was determined by MTT *** results clearly proved that biosynthesized AgNPs inhibited proliferation of HeLA cell line with an IC50 of 87.32±1.43g/mL and antibacterial activity.

关键词： silver nanoparticles Green synthesis Cytotoxicity Antioxidant DPPH FRAP XRD Nothapodytes nimmoniana

silver nanoparticles Supported on TiO_(2) and Their Antibacterial Properties:Effect of Surface Confinement and Nonexistence of Plasmon Resonance

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Materials Sciences and Applications 2014年第12期5卷 895-903页

作者： Zoe Vineth Quinones-Jurado Miguel ángel Waldo-Mendoza Hugo Marcelo Aguilera-Bandin Edgar Giovanny Villabona-Leal Elsa Cervantes-González Elías Pérez Innovation and Development in Advanced Materials POLYnnova GroupSan Luis PotosíMéxico A Schulman of México San Luis PotosíMéxico Institute of Physic Autonomous University of San Luis PotosíSan Luis PotosíMéxico Academic Coordination Altiplano RegionAutonomous University of San Luis PotosíSan Luis PotosíMéxico

Ag/TiO2 nanocomposites are usually regarded as an effective synergy for high antimicrobial performance under ultraviolet-visible light conditions. This study confirmed that the surface plasmon resonance of Ag NPs plays an important role in relation to the NPs size and consequently with the antibacterial effect of the nanocomposite. We observed that under visible light the reactivity of TiO2 cannot be amplified when it is supporting Ag NPs that have an inactive photocatalytically surface. The results confirmed that the antimicrobial effectiveness of nanocomposite based on Ag NPs supported-TiO2 is closely associated to the contact surface area and to the electronic performance of the noble metal.

关键词： Ag-TiO_(2) Antibacterial silver nanoparticles Surface Confinement