Biosynthesis of Silver and Gold Nanoparticles Using Aqueous Extract of Codonopsis pilosula Roots for Antibacterial and Catalytic Applications

In this study, biogenic silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were synthesized by a green approach using an aqueous extract from Codonopsis pilosula (CP) roots as a reducing and stabilizing agent. The formation of CP-AgNPs and CP-AuNPs was confirmed and optimized by UV-Vis spectroscopy. The CP-AgNPs and CP-AuNPs obtained under optimum conditions of metal ion concentration, reaction temperature, and reaction time were characterized by high-resolution transition electron microscopy (HR-TEM), selected area electron diffraction (SAED) analysis, field-emission scan electron microscopy (FE-SEM), powder X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, dispersive X-ray spectroscopy (EDX), and dynamic light scattering (DLS) method. It has been found that the biosynthesized CP-AgNPs and CP-AuNPs were formed in spherical shape with an average size of 10±2.5 nm and 20±3.2 nm, respectively. The biosynthesized metallic nanoparticles exhibited selective bacterial activity against three bacterial strains including two Gram-positive bacteria of Bacillus subtilis and Staphylococcus aureus and one Gram-negative bacteria of Escherichia coli. Meanwhile, there was no antibacterial activity detected toward Gram-negative Salmonella enteritidis. CP-AgNPs and CP-AuNPs also manifested an excellent catalytic performance in the reduction of 1,4-dinitrobenzene, 2-nitrophenol, 3-nitrophenol, and 4-nitrophenol.

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Polysulfide/Graphene Nanocomposite Film for Simultaneous Electrochemical Determination of Cadmium and Lead Ions

NANO ◽

10.1142/s179329201850090x ◽

2018 ◽

Vol 13 (08) ◽

pp. 1850090 ◽

Cited By ~ 4

Author(s):

Ruyuan Jiang ◽

Niantao Liu ◽

Yuhong Su ◽

Sanshuang Gao ◽

Xamxikamar Mamat ◽

...

Keyword(s):

Electron Microscopy ◽

Heavy Metal ◽

Photoelectron Spectroscopy ◽

Metal Ion ◽

Electrochemical Sensors ◽

Anodic Stripping Voltammetry ◽

Pyrolytic Graphite ◽

Stripping Voltammetry ◽

Ion Concentration ◽

X Ray

An integrative electroanalytical method was developed for detecting Cd[Formula: see text] and Pb[Formula: see text] ions in aqueous solutions. Polysulfide/graphene (RGO-S) nanocomposites were prepared and their performance as electrochemical sensors for Cd[Formula: see text] and Pb[Formula: see text] was evaluated. The RGO-S nanocomposite was carefully characterized by scanning electron microscopy with energy-dispersive X-ray spectrometry, transmission electron microscopy, and X-ray photoelectron spectroscopy. The as-prepared RGO-S was incorporated into a pyrolytic graphite electrode (RGO-S/PGE) and used for detecting trace amount of Cd[Formula: see text] and Pb[Formula: see text] by differential pulse anodic stripping voltammetry. Under optimal conditions, the stripping peak current of RGO-S/PGE varies linearly with heavy metal ion concentration in the ranges 2.0–300[Formula: see text][Formula: see text]g L[Formula: see text] for Cd[Formula: see text] and 1.0–300[Formula: see text][Formula: see text]g L[Formula: see text] for Pb[Formula: see text]. The limits of detection for Cd[Formula: see text] and Pb[Formula: see text] were estimated to be about 0.67[Formula: see text][Formula: see text]g L[Formula: see text] and 0.17[Formula: see text][Formula: see text]g L[Formula: see text], respectively. The prepared electrochemical heavy-metal-detecting electrode provides good repeatability and reproducibility with high sensitivity, making it a suitable candidate for monitoring Cd[Formula: see text] and Pb[Formula: see text] concentrations in aqueous environmental samples.

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PHYTOSYNTHESIS AND CHARACTERIZATION OF SILVER NANOPARTICLES FROM RUELLIA TUBEROSA (L.): EFFECT OF PHYSICOCHEMICAL PARAMETERS

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2021.v14i12.42020 ◽

2021 ◽

pp. 31-38

Author(s):

HARIKA M ◽

RADHIKA P

Keyword(s):

Silver Nanoparticles ◽

Metal Ion ◽

Incubation Temperature ◽

Ion Concentration ◽

Gas Chromatography Mass Spectrometry ◽

Face Centered Cubic ◽

X Ray ◽

Synthesis Of Nanoparticles ◽

Vis Spectroscopy ◽

Tuber Extract

Objective: The current study focused on synthesizing silver nanoparticles (AgNPs) using Ruellia tuberosa aqueous tuber extract (RTTE) and silver nitrate (AgNO3) solution. Methods: AgNPs were synthesized using an aqueous tuber extract of the medicinal herb R. tuberosa (L.). The existence of significant phytoconstituents involved in synthesizing the AgNPs was determined using the gas chromatography–mass spectrometry (GC–MS) study. We evaluated the physical and chemical parameters such as the effect of time, temperature, metal ion concentration, crude aqueous tuber extract concentration, and pH in the synthesis of nanoparticles. The AgNPs were characterized using ultraviolet (UV)–Vis spectroscopy, field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscope (HRTEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) techniques. Results: R. tuberosa tuber extract was rich in various phytochemical constituents which were identified by GC–MS. For biosynthesis, the optimal values were 1 mM AgNO3concentration, 0.1 mL of aqueous tuber extract, and a 40 min incubation temperature of 70°C. The existence of a characteristic surface plasmon resonance (SPR) peak at 421 nm indicated the biosynthesis of AgNPs using UV–Vis spectroscopy. At higher temperatures and alkaline pH, the development of AgNPs increased overtime and remained stable up to 4 weeks. FESEM, EDX, HRTEM, SAED, and XRD analysis revealed that most AgNPs were spherical, with an average size distribution of 34.9 nm and a crystalline phase, face-centered cubic lattice. Infrared (FTIR) spectroscopic analysis revealed that hydroxyl and amino functional groups were involved in the biosynthesis and stabilization of AgNPs. Conclusion: The synthesis of AgNPs from R. tuberosa aqueous tuber extract was a cost-effective process and environmental friendly.

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Investigating the Possibility of Green Synthesis of Silver Nanoparticles Using Vaccinium arctostaphlyos Extract and Evaluating Its Antibacterial Properties

BioMed Research International ◽

10.1155/2021/5572252 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Sedighe Khodadadi ◽

Nafiseh Mahdinezhad ◽

Bahman Fazeli-Nasab ◽

Mohammad Javad Heidari ◽

Baratali Fakheri ◽

...

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Ftir Spectroscopy ◽

Aqueous Extract ◽

Nitrate Solution ◽

Antibacterial Properties ◽

Silver Nitrate Solution ◽

X Ray Diffraction ◽

X Ray ◽

Vis Spectroscopy

Objective. Vaccinium genus plants have medicinal value, of which Vaccinium arctostaphylos (Caucasian whortleberry or Qare-Qat in the local language) is the only available species in Iran. Public tendency to use herbal remedies and natural products such as synthesized nanoparticles is increasing due to the proof of the destructive side effects of chemical drugs. Nanosilver products have been effective against more than 650 microbe types. This study was aimed at assessing the possibility of green synthesis of silver nanoparticles using Vaccinium arctostaphylos aqueous extract and at evaluating its antibacterial properties, as well. Materials and Methods. In order to synthesize silver nanoparticles, different volumes of Vaccinium arctostaphylos aqueous extract (3, 5, 10, 15, and 30 ml) were assessed with different silver nitrate solution concentrations (0.5, 1, 3, 5, and 10 mM) and different reaction time durations (1, 3, 5, 10, and 20 minutes) at room temperature using a rotary shaker with a speed of 150 rpm. Ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction analysis (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were carried out. The antibacterial activity of the aqueous extract and the synthesized nanoparticles was evaluated, as well. Results. Silver nanoparticle formation process was confirmed with XRD analysis, transmission electron microscopy (TEM), and FTIR spectroscopy. The UV-Vis spectroscopy of silver colloidal nanoparticles showed a surface plasmon resonance peak at 443 nm under optimal conditions (3 ml aqueous extract volume, 1 mM silver nitrate solution concentration, and 3 min reaction time under sunlight exposure). The reduction of silver ions to silver nanoparticles in solution was confirmed, as well. Based on X-ray diffraction analysis, the size of silver nanoparticles was in the range of 7-16 nm. TEM images showed an even distribution of silver nanoparticles, with a spherical shape. FTIR spectroscopy demonstrated the presence of different functional groups of oxygenated compounds such as carboxyl, hydroxyl, and nitrogenous groups. The antibacterial properties of the synthesized nanoparticles were confirmed. Conclusion. The synthesized nanoparticles showed more antibacterial properties against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) than gram-negative ones (Escherichia coli and Salmonella enteritidis).

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Synthesis of Gold Nanoparticles Stabilized in Dextran Solution by Gamma Co-60 Ray Irradiation and Preparation of Gold Nanoparticles/Dextran Powder

Journal of Chemistry ◽

10.1155/2017/6836375 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Phan Ha Nu Diem ◽

Doan Thi Thu Thao ◽

Dang Van Phu ◽

Nguyen Ngoc Duy ◽

Hoang Thi Dong Quy ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Gold Nanoparticles ◽

Spherical Shape ◽

Powder Form ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Influence Of Ph ◽

Dextran Solution

Gold nanoparticles (AuNPs) in spherical shape with diameter of 6–35 nm stabilized by dextran were synthesized by γ-irradiation method. The AuNPs were characterized by UV-Vis spectroscopy and transmission electron microscopy. The influence of pH, Au3+ concentration, and dextran concentration on the size of AuNPs was investigated. Results indicated that the smallest AuNPs size (6 nm) and the largest AuNPs size (35 nm) were obtained for pH of 1 mM Au3+/1% dextran solution of 5.5 and 7.5, respectively. The smaller Au3+ concentration favored smaller size and conversely the smaller dextran concentration favored bigger size of AuNPs. AuNPs powders were prepared by spay drying, coagulation, and centrifugation and their sizes were also evaluated. The purity of prepared AuNPs powders was also examined by energy dispersive X-ray (EDX) analysis. Thus, the as-prepared AuNPs stabilized by biocompatible dextran in solution and/or in powder form can be potentially applied in biomedicine and pharmaceutics.

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Study of Methylene Blue Degradation by Gold Nanoparticles Synthesized within Natural Zeolites

Journal of Nanomaterials ◽

10.1155/2016/9541683 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Ericka Rodríguez León ◽

Eduardo Larios Rodríguez ◽

César Rodríguez Beas ◽

Germán Plascencia-Villa ◽

Ramón Alfonso Iñiguez Palomares

Keyword(s):

Electron Microscopy ◽

Methylene Blue ◽

Gold Nanoparticles ◽

Methylene Blue Degradation ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Scanning Transmission ◽

Type Zeolite ◽

Natural Clinoptilolite

We carried out thein situsynthesis of gold nanoparticles inside a natural clinoptilolite-type zeolite matrix, using ascorbic acid as reducing agent. The microstructure of both zeolite and zeolite-gold nanocomposite was characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Scanning Transmission Electron Microscopy (STEM), and Energy-Dispersive X-ray Spectroscopy (EDS) techniques. Size distribution as assessed by STEM indicated that 60% of gold nanoparticles measured less than 2.5 nm. Determination of the surface area by the BET method revealed a specific value of 27.35 m2/g. The catalytic activity of zeolite-gold regarding methylene blue degradation under different light-exposing conditions was evaluated by UV-Vis spectroscopy. The results indicated that 50% degradation was achieved in only 11 min in presence of sunlight. This reaction was faster in comparison with those obtained using a white LED light. A notable aspect of this study is that catalysis was carried out without the addition of any strong reducing agents, such as sodium borohydride (NaBH4).

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Synthesis and characterization of Fe, Co, and Ni colloids in 2-mercaptoethanol

Nanomaterials and Nanotechnology ◽

10.1177/1847980420966883 ◽

2020 ◽

Vol 10 ◽

pp. 184798042096688

Author(s):

Galo Cárdenas-Triviño ◽

Sergio Triviño-Matus

Keyword(s):

Electron Microscopy ◽

Electron Diffraction ◽

Colloidal Dispersions ◽

Synthesis And Characterization ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Chemical Liquid Deposition ◽

Liquid Deposition

Metal colloids in 2-mercaptoethanol using nanoparticles (NPs) of iron (Fe), cobalt (Co), and nickel (Ni) were prepared by chemical liquid deposition method. Transmission electron microscopy, electron diffraction, UV-VIS spectroscopy, and scanning electron microscopy with electron dispersive X-ray spectroscopy characterized the resulting colloidal dispersions. The NPs exhibited sizes with ranges from 9.8 nm for Fe, 3.7 nm for Co, and 7.2 nm for Ni. The electron diffraction shows the presence of the metals in its elemental state Fe (0), Co (0), and Ni (0) and also some compounds FeO (OH), CoCo2S4, and NiNi2S4.

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Magnetically Recyclable Wool Keratin Modified Magnetite Powders for Efficient Removal of Cu2+ Ions from Aqueous Solutions

Nanomaterials ◽

10.3390/nano11051068 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1068

Author(s):

Xinyue Zhang ◽

Yani Guo ◽

Wenjun Li ◽

Jinyuan Zhang ◽

Hailiang Wu ◽

...

Keyword(s):

Electron Microscopy ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Surface Area ◽

Ion Concentration ◽

Bet Surface Area ◽

Chemical Compositions ◽

Ion Adsorption ◽

X Ray ◽

Wool Keratin

The treatment of wastewater containing heavy metals and the utilization of wool waste are very important for the sustainable development of textile mills. In this study, the wool keratin modified magnetite (Fe3O4) powders were fabricated by using wool waste via a co-precipitation technique for removal of Cu2+ ions from aqueous solutions. The morphology, chemical compositions, crystal structure, microstructure, magnetism properties, organic content, and specific surface area of as-fabricated powders were systematically characterized by various techniques including field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), thermogravimetric (TG) analysis, and Brunauer–Emmett–Teller (BET) surface area analyzer. The effects of experimental parameters such as the volume of wool keratin hydrolysate, the dosage of powder, the initial Cu2+ ion concentration, and the pH value of solution on the adsorption capacity of Cu2+ ions by the powders were examined. The experimental results indicated that the Cu2+ ion adsorption performance of the wool keratin modified Fe3O4 powders exhibited much better than that of the chitosan modified ones with a maximum Cu2+ adsorption capacity of 27.4 mg/g under favorable conditions (0.05 g powders; 50 mL of 40 mg/L CuSO4; pH 5; temperature 293 K). The high adsorption capacity towards Cu2+ ions on the wool keratin modified Fe3O4 powders was primarily because of the strong surface complexation of –COOH and –NH2 functional groups of wool keratins with Cu2+ ions. The Cu2+ ion adsorption process on the wool keratin modified Fe3O4 powders followed the Temkin adsorption isotherm model and the intraparticle diffusion and pseudo-second-order adsorption kinetic models. After Cu2+ ion removal, the wool keratin modified Fe3O4 powders were easily separated using a magnet from aqueous solution and efficiently regenerated using 0.5 M ethylene diamine tetraacetic acid (EDTA)-H2SO4 eluting. The wool keratin modified Fe3O4 powders possessed good regenerative performance after five cycles. This study provided a feasible way to utilize waste wool textiles for preparing magnetic biomass-based adsorbents for the removal of heavy metal ions from aqueous solutions.

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Effects of Different Surfactant Charges on the Formation of Gold Nanoparticles by the LASiS Method

Materials ◽

10.3390/ma14112937 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2937

Author(s):

Muhammad Zulfajri ◽

Wei-Jie Huang ◽

Genin-Gary Huang ◽

Hui-Fen Chen

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Gold Nanoparticles ◽

Laser System ◽

Synthesis Process ◽

Au Nps ◽

Laser Fluences ◽

Transmission Electron ◽

Vis Spectroscopy ◽

532 Nm

The laser ablation synthesis in solution (LASiS) method has been widely utilized due to its significant prospects in laser microprocessing of nanomaterials. In this study, the LASiS method with the addition of different surfactant charges (cationic CTAB, nonionic TX-100, and anionic SDS) was used to produce Au NPs. An Nd:YAG laser system at 532 nm excitation with some synthetic parameters, including different laser fluences, ablation times, and surfactant concentrations was performed. The obtained Au NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, and zeta potential analyzer. The Au NPs exhibited the maximum absorption peak at around 520 nm for all samples. The color of Au NPs was changed from red to reddish by increasing the laser fluence. The surfactant charges also played different roles in the Au NPs’ growth during the synthesis process. The average sizes of Au NPs were found to be 8.5 nm, 5.5 nm, and 15.5 nm with the medium containing CTAB, TX-100, and SDS, respectively. Besides, the different surfactant charges induced different performances to protect Au NPs from agglomeration. Overall, the SDS and CTAB surfactants exhibited higher stability of the Au NPs compared to the Au NPs with TX-100 surfactant.

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Synthesis and Study the Properties of a Solar Cell of Gold Nanoparticles Prepared in a Simple Chemical Way

NeuroQuantology ◽

10.14704/nq.2021.19.11.nq21176 ◽

2021 ◽

Vol 19 (11) ◽

pp. 66-71

Author(s):

Maithm A. Obaid ◽

Suha A Fadaam ◽

Osama S. Hashim

Keyword(s):

Electron Microscopy ◽

Gold Nanoparticles ◽

Chemical Method ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

Casting Method ◽

X Ray ◽

Transmission Electron ◽

Simple Chemical ◽

Scanning Electron

The aim of this study is to prepare gold nanoparticles by a simple chemical method at a temperature of 70°C. The solution was dried on glass basest by Casting method, the rate of five drops per sample At a temperature 100 C. Then the structural and optical properties have been confirmed by X-ray diffraction, scanning electron microscopy (SEM) and Transmission Electron microscope (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and spectrum.

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Cloning, expression, purification, crystallization and preliminary X-ray diffraction of a lysine-specific permease fromPseudomonas aeruginosa

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x14017865 ◽

2014 ◽

Vol 70 (10) ◽

pp. 1362-1367 ◽

Cited By ~ 3

Author(s):

Emmanuel Nji ◽

Dianfan Li ◽

Declan A. Doyle ◽

Martin Caffrey

Keyword(s):

Metal Ion ◽

Cell Volume Regulation ◽

Ion Concentration ◽

Size Exclusion ◽

Substrate Selectivity ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Exclusion Chromatography

The prokaryotic lysine-specific permease (LysP) belongs to the amino acid–polyamine–organocation (APC) transporter superfamily. In the cell, members of this family are responsible for the uptake and recycling of nutrients, for the maintenance of a constant internal ion concentration and for cell volume regulation. The detailed mechanism of substrate selectivity and transport of L-lysine by LysP is not understood. A high-resolution crystal structure would enormously facilitate such an understanding. To this end, LysP fromPseudomonas aeruginosawas recombinantly expressed inEscherichia coliand purified to near homogeneity by immobilized metal ion-affinity chromatography (IMAC) and size-exclusion chromatography (SEC). Hexagonal- and rod-shaped crystals were obtained in the presence of L-lysine and the L-lysine analogue L-4-thialysine by vapour diffusion and diffracted to 7.5 Å resolution. The diffraction data were indexed in space groupP21, with unit-cell parametersa= 169.53,b= 169.53,c= 290.13 Å, γ = 120°.

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