scholarly journals Green synthesis of copper nanoparticles by Citrus limon fruits extract, characterization and antibacterial activity

2021 ◽  
Author(s):  
CI Chemistry International
Keyword(s):  
Green Synthesis ◽  
Copper Nanoparticles ◽  
Spherical Particles ◽  
Citrus Limon ◽  
Electron Microscopic ◽  
Practical Applications ◽  
Transmission Electron ◽  
Green Route ◽  
Average Size ◽  
Reported Data

In view of advantages of green synthesis, a novel green route for the synthesis and stabilization of copper nanoparticles (CuNPs) using aqueous extract of Citrus limon fruits at room temperature was reported. The formation of CuNPs is monitored by recording the UV–vis absorption spectra for surface Plasmon resonance (SPR) peak (∼579 nm). X-ray diffraction (XRD) pattern of the CuNPs agrees with the reported data for Cu metal and the crystallite average size is ~30 nm. Scanning and transmission electron microscopic (SEM and TEM) show uniform spherical particles obtained by this green method. The antimicrobial activity is found to be effective of CuNPs. Results revealed that the green synthesis is an efficient for the preparation of CuNPs as an active antimicrobial agent for practical applications.

scholarly journals Protoenzymes: The Case of Hyperbranched Polymer-Scaffolded ZnS Nanocrystals

2020 ◽  
Author(s):  
Irena Mamajanov ◽  
Melina Caudan ◽  
Tony Z. Jia
Keyword(s):  
Hyperbranched Polymer ◽  
Metal Sulfide ◽  
Reaction Network ◽  
High Photocatalytic Activity ◽  
Spherical Particles ◽  
Transmission Electron ◽  
Eosin B ◽  
Polymer Supported ◽  
Zns Nanocrystals ◽  
Average Size

<p>Enzymes could be described as small-molecule, metal, or cluster catalysts augmented by biopolymeric scaffolds. It is conceivable that early in chemical evolution, ancestral enzymes opted for simpler, easier to assemble scaffolds. Herein, we describe such possible protoenzymes: hyperbranched polymer-scaffolded metal-sulfide nanocrystals. Hyperbranched polyethyleneimine (HyPEI) and glycerol citrate polymer-supported ZnS nanocrystals (NCs) are formed in a simple, abiotically plausible process. Transmission electron microscopy (TEM) analyses of HyPEI-supported NCs reveals spherical particles with an average size of 10nm that undergo only a modest aggregation over a 14-day incubation. The polymer-supported ZnS NCs are shown to possess a high photocatalytic activity in an eosin B photodegradation assay, making them an attractive model for the study of the origin of life under the “Zn world” theory dominated by a photocatalytic proto-metabolic redox reaction network. The catalyst, however, could be easily adapted to apply broadly to different protoenzymatic systems.</p>

Synthesis of Copper Nanoparticles at Room Temperature Using Hydrazine in Glycerol

2013 ◽  
Vol 481 ◽  
pp. 21-26 ◽  
Author(s):  
Huei Ruey Ong ◽  
Maksudur Rahman Khan ◽  
Ridzuan Ramli ◽  
Rosli Mohd Yunus
Keyword(s):  
Copper Nanoparticles ◽  
Room Temperature ◽  
Red Wine ◽  
Copper Chloride ◽  
Reduction Process ◽  
Stability Study ◽  
Ambient Conditions ◽  
Transmission Electron ◽  
Average Size ◽  
Hydrazine Solution

Copper nanoparticles (CuNPs) have been prepared by the reduction of copper chloride in glycerol using hydrazine at ambient conditions. The reduction process takes place under vigorous stirring for 8 h. The formation of CuNPs and size were confirmed by UV/Vis analysis and TEM imaging respectively. The experiment result showed that, 7.062 mM of hydrazine solution and 0.0147 mM of Cu2+ solution were needed to synthesize narrow size monodisperseCuNPs.The presence of nanoparticle was found after an induction period of 4 h and further reaction time, complete Cu0 state nanoparticle was obtained as deep red wine colour was observed. Stability study of CuNPs showed that the nanoparticles were stable up to 4 days. The particle size of the nanoparticles have been analysed by transmission electron microscopy (TEM) and the average size of CuNPs was in the range 2 to 10 nm.

Receiving Copper Nanoparticles: Experiment and Modelling

2019 ◽  
Vol 288 ◽  
pp. 140-147 ◽  
Author(s):  
Andrey V. Nomoev ◽  
Erzhena C. Khartaeva ◽  
Natalia V. Yumozhapova ◽  
Tumen G. Darmaev ◽  
S.P. Bardakhanov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Copper Nanoparticles ◽  
Pure Copper ◽  
Current Strength ◽  
X Ray Diffraction ◽  
X Ray ◽  
Embedded Atom ◽  
Transmission Electron ◽  
Average Size

The copper nanoparticles were obtained by evaporating the metal by the relativistic electron beam. The average size of synthesized particles was about 120 nm. They were characterized by X-ray diffraction, transmission electron microscopy. The results of the X-ray diffraction showed high content of the pure copper for closed setup with an inert gas. Transmission electron microscopy cleared some particles to have an icosahedral structure. These nanoparticles were obtained when the target was exposed by the beam with the highest current strength used in the experiment and the highest cooling of the copper vapor. The process of copper nanoparticle formation by the molecular dynamic method using EAM – potentials (potentials in the Embedded Atom Method form) was studied.

scholarly journals Green Synthesis of Silver Nanoparticles Using Astragalus tribuloides Delile. Root Extract: Characterization, Antioxidant, Antibacterial, and Anti-Inflammatory Activities

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2383
Author(s):  
Majid Sharifi-Rad ◽  
Pawel Pohl ◽  
Francesco Epifano ◽  
José M. Álvarez-Suarez
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Total Phenolics ◽  
Cost Effective ◽  
Root Extract ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
High Efficient ◽  
Anti Inflammatory ◽  
Average Size

Today, the green synthesis of metal nanoparticles is a promising strategy in material science and nanotechnology. In this research, silver nanoparticles (AgNPs) were synthesized through the high-efficient, cost-effective green and facile process, using the Astragalus tribuloides Delile. root extract as a bioreduction and capping agent at room temperature. UV–Vis spectroscopy was applied for the investigation of the reaction proceedings. To characterize the greenly synthesized AgNPs, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), and transmission electron microscopy (TEM) analyses were utilized. In addition, the total phenolics and flavonoids contents, antioxidant, antibacterial, and anti-inflammatory activities of the greenly synthesized AgNPs and the A. tribuloides root extract were evaluated. The results indicated that the AgNPs had spherical morphology and crystalline structure with the average size of 34.2 ± 8.0 nm. The total phenolics and flavonoids contents of the greenly synthesized AgNPs were lower than those for the A. tribuloides root extract. The resultant AgNPs exhibited the appropriate antioxidant activity (64%) as compared to that for the A. tribuloides root extract (47%). The antibacterial test approved the higher bactericidal activity of the resulting AgNPs on the Gram-positive and Gram-negative bacteria in comparison to the A. tribuloides root extract. Considering the anti-inflammatory activity, the greenly synthesized AgNPs showed a stranger effect than the A. tribuloides root extract (82% versus 69% at 500 μg/mL). Generally, the AgNPs that were fabricated by using the A. tribuloides root extract had appropriate antioxidant, antibacterial, and anti-inflammatory activities and, therefore, can be considered as a promising candidate for various biomedical applications.

Durian Peeling Extract Mediated Green Synthesis of Silver Nanoparticles

2014 ◽  
Vol 875-877 ◽  
pp. 18-22 ◽  
Author(s):  
Fueangfahkan Chutrakulwong ◽  
Kheamrutai Thamaphat
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Spherical Particles ◽  
Main Role ◽  
X Ray Diffraction ◽  
Synthesis Mechanism ◽  
Durio Zibethinus ◽  
Transmission Electron ◽  
Fcc Phase ◽  
Durian Rind

In this work, silver nanoparticles (AgNPs) were successfully synthesized from AgNO3 through a simple and eco-friendly method, also called the green synthesis, using Mon Thong durian (Durio zibethinus L.) peeling extract. The main role in synthesis mechanism of AgNPs is using polysaccharides in durian rind as a reducing agent as well as stabilizer. The appearance of a yellowish-brown color in mixture of AgNO3 solution and durian rind extract is the indication of formation of AgNPs. The synthesized AgNPs were characterized by UV-visible spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD) spectrometry. The AgNPs were found to be polycrystalline in nature and spherical particles with diameter of 11.7 ± 3.2 nm. The crystallinity with fcc phase is evidenced by clear lattice fringes in SAED pattern and diffraction peaks in the XRD pattern corresponding to the (111), (200), (220), and (311) planes.

Preparation and Properties of Poly(N-vinylcarbazole) and MWCNT Nanocomposites

2008 ◽  
Vol 8 (4) ◽  
pp. 1751-1756
Author(s):  
Arjun Maity ◽  
Mukul Biswas
Keyword(s):  
Weight Ratio ◽  
Microscopic Analysis ◽  
Xrd Analysis ◽  
Spherical Particles ◽  
Electron Microscopic ◽  
Irregular Shapes ◽  
Transmission Electron ◽  
Current Voltage ◽  
Varied Form ◽  
Scanning Electron Microscopic Analysis

N-vinylcarbazole (NVC) was polymerized in bulk through the interaction of multi-walled carbon nanotube (MWCNT) without any extraneous catalyst. A PNVC-MWCNT composite was isolated by MeOH precipitation of a polymerization system containing NVC and MWCNT at melting temperature of the monomer. The inclusion of PNVC in the composite was endorsed by the FTIR study. TG analysis revealed the thermal stability trend as MWCNT > PNVC-MWCNT composite > PNVC. DTA showed two exothermic peaks at 427 °C and 607 °C in the PNVC-MWCNT composite. Transmission electron microscopic analyses of MWCNT revealed presence of tubular MWCNT particles with diameters in nm range while the corresponding analysis for the composite showed the formation of spherical dark polymer particles encapsulating cylindrical MWCNT moieties with some ends of uncoated MWCNT tubes (light shades) protruding out of the dark spherical particles. Scanning electron microscopic analysis revealed presence of tubular CNT particles entangled with the composite particles of irregular shapes and sizes. XRD analysis revealed no additional crystalline peaks for PNVC in the composite. In contrast to PNVC homopolymer (10–12–10–16 S/cm), the dc conductivity values of the composite varied form 1.3 to 33 S/cm depending upon the weight ratio of MWCNT and PNVC in the composite. Current–voltage characteristics of the composite showed a linear variation and conductivity–temperature studies revealed an increase in conductivity by 35% in the temperature range 150–220 °C.

scholarly journals Protoenzymes: The Case of Hyperbranched Polymer-Scaffolded ZnS Nanocrystals

Life ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 150
Author(s):  
Irena Mamajanov ◽  
Melina Caudan ◽  
Tony Z. Jia
Keyword(s):  
Hyperbranched Polymer ◽  
Metal Sulfide ◽  
Reaction Network ◽  
High Photocatalytic Activity ◽  
Spherical Particles ◽  
Transmission Electron ◽  
Eosin B ◽  
Polymer Supported ◽  
Zns Nanocrystals ◽  
Average Size

Enzymes are biological catalysts that are comprised of small-molecule, metal, or cluster catalysts augmented by biopolymeric scaffolds. It is conceivable that early in chemical evolution, ancestral enzymes opted for simpler, easier to assemble scaffolds. Herein, we describe such possible protoenzymes: hyperbranched polymer-scaffolded metal-sulfide nanocrystals. Hyperbranched polyethyleneimine (HyPEI) and glycerol citrate polymer-supported ZnS nanocrystals (NCs) are formed in a simple process. Transmission electron microscopy (TEM) analyses of HyPEI-supported NCs reveal spherical particles with an average size of 10 nm that undergo only a modest aggregation over a 14-day incubation. The polymer-supported ZnS NCs are shown to possess a high photocatalytic activity in an eosin B photodegradation assay, making them an attractive model for the study of the origin of life under the “Zn world” theory dominated by a photocatalytic proto-metabolic redox reaction network. The catalyst, however, could be easily adapted to apply broadly to different protoenzymatic systems.

The effects of different polymerization agents on structural and optical properties of (K0.5Na0.5)NbO3 nanopowders synthesized by a facile green route

2014 ◽  
Vol 28 (28) ◽  
pp. 1450224 ◽  
Author(s):  
Gh. H. Khorrami ◽  
A. Kompany ◽  
A. Khorsand Zak
Keyword(s):  
Optical Properties ◽  
Sol Gel ◽  
Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Energy Band Gap ◽  
Structural And Optical Properties ◽  
Transmission Electron ◽  
Green Route ◽  
Xrd Patterns ◽  
Average Size

( K 0.5 N 0.5) NbO 3 lead-free nanopowders were synthesized by a modified sol–gel method in different media: gelatin, starch and chitosan, as polymerization and stabilizer agents. The proper temperature needed for calcinating the prepared gel was obtained using thermogravometric analysis (TGA). Structural and optical properties of the prepared powders were investigated and compared using X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV-Vis diffused reflectance spectroscopy. The XRD patterns of the synthesized samples confirmed the formation of the orthorhombic structure at 600°C calcination temperature with no remarkable extra peaks. TEM images showed that the morphologies of the particles prepared in the three different media are cubic with the average size of about 69, 34 and 49 nm for gelatin, starch and chitosan, respectively. The value of the energy band gap of the samples was calculated by diffused reflectance spectroscopy, using Kubelka–Munk method. Our results showed that the type of the polymerization agent is important in preparing KNN nanoparticles and affects the structural and optical properties of the synthesized samples.

scholarly journals Nanofibrillated Cellulose and Copper Nanoparticles Embedded in Polyvinyl Alcohol Films for Antimicrobial Applications

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Tuhua Zhong ◽  
Gloria S. Oporto ◽  
Jacek Jaczynski ◽  
Changle Jiang
Keyword(s):  
Polyvinyl Alcohol ◽  
Copper Nanoparticles ◽  
Chemical Reduction ◽  
Antimicrobial Properties ◽  
Nanofibrillated Cellulose ◽  
Microbial Reduction ◽  
Nanocomposite Films ◽  
Transmission Electron ◽  
Average Size ◽  
Thermoplastic Resins

Our long-term goal is to develop a hybrid cellulose-copper nanoparticle material as a functional nanofiller to be incorporated in thermoplastic resins for efficiently improving their antimicrobial properties. In this study, copper nanoparticles were first synthesized through chemical reduction of cupric ions on TEMPO nanofibrillated cellulose (TNFC) template using borohydride as a copper reducing agent. The resulting hybrid material was embedded into a polyvinyl alcohol (PVA) matrix using a solvent casting method. The morphology of TNFC-copper nanoparticles was analyzed by transmission electron microscopy (TEM); spherical copper nanoparticles with average size of 9.2 ± 2.0 nm were determined. Thermogravimetric analysis and antimicrobial performance of the films were evaluated. Slight variations in thermal properties between the nanocomposite films and PVA resin were observed. Antimicrobial analysis demonstrated that one-week exposure of nonpathogenicEscherichia coliDH5αto the nanocomposite films results in up to 5-log microbial reduction.

scholarly journals Protoenzymes: The Case of Hyperbranched Polymer-Scaffolded ZnS Nanocrystals

2020 ◽  
Author(s):  
Irena Mamajanov ◽  
Melina Caudan ◽  
Tony Z. Jia
Keyword(s):  
Hyperbranched Polymer ◽  
Metal Sulfide ◽  
Reaction Network ◽  
High Photocatalytic Activity ◽  
Spherical Particles ◽  
Transmission Electron ◽  
Eosin B ◽  
Polymer Supported ◽  
Zns Nanocrystals ◽  
Average Size

<p>Enzymes could be described as small-molecule, metal, or cluster catalysts augmented by biopolymeric scaffolds. It is conceivable that early in chemical evolution, ancestral enzymes opted for simpler, easier to assemble scaffolds. Herein, we describe such possible protoenzymes: hyperbranched polymer-scaffolded metal-sulfide nanocrystals. Hyperbranched polyethyleneimine (HyPEI) and glycerol citrate polymer-supported ZnS nanocrystals (NCs) are formed in a simple, abiotically plausible process. Transmission electron microscopy (TEM) analyses of HyPEI-supported NCs reveals spherical particles with an average size of 10nm that undergo only a modest aggregation over a 14-day incubation. The polymer-supported ZnS NCs are shown to possess a high photocatalytic activity in an eosin B photodegradation assay, making them an attractive model for the study of the origin of life under the “Zn world” theory dominated by a photocatalytic proto-metabolic redox reaction network. The catalyst, however, could be easily adapted to apply broadly to different protoenzymatic systems.</p>

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