scholarly journals Chitosan-Reinforced MFC/NFC Aerogel and Antibacterial Property

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Huanlei Yang ◽  
Shuxin Zhang ◽  
Jinhua Yan
Keyword(s):  
Antibacterial Activity ◽  
Antibacterial Property ◽  
Water Stability ◽  
Chemical Bonds ◽  
Ag Nps ◽  
Water Sensitivity ◽  
Reinforcing Agent ◽  
Good Potential ◽  
Potential Substrate ◽  
Nanoparticles Of Silver

MFC/NFC aerogel has water sensitivity, and it should be improved in strength in water before application. Chitosan was investigated as a MFC/NFC aerogel reinforcing agent in this paper. The reinforced aerogel showed slightly tighter structure and very good water stability and mechanical strength. FTIR disclosed the chemical bonds formed between chitosan and cellulose. Nanoparticles of silver (Ag-NPs) were loaded using the reinforced aerogel. The excellent Ag-NP monodistribution on the aerogel was expressed by TEM. Both chitosan-reinforced Ag-NPs loaded MFC aerogel and NFC aerogel and expressed great antibacterial activity, though reinforced MFC aerogel exhibited better properties, like higher BET, lighter density, more Ag-NP loading, and better distribution, than NFC aerogel in this research. Chitosan-reinforced MFC aerogel is a good potential substrate for nanoparticle loading and biocomposite making.

scholarly journals Antibacterial activity of royal jelly-mediated green synthesized silver nanoparticles

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Susanna Gevorgyan ◽  
Robin Schubert ◽  
Mkrtich Yeranosyan ◽  
Lilit Gabrielyan ◽  
Armen Trchounian ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Green Synthesis ◽  
Royal Jelly ◽  
Fluorescence Emission ◽  
Spherical Particles ◽  
Ag Nps ◽  
Gram Negative ◽  
Green Synthesized Silver Nanoparticles ◽  
Higher Sensitivity

AbstractThe application of green synthesis in nanotechnology is growing day by day. It’s a safe and eco-friendly alternative to conventional methods. The current research aimed to study raw royal jelly’s potential in the green synthesis of silver nanoparticles and their antibacterial activity. Royal jelly served as a reducing and oxidizing agent in the green synthesis technology of colloidal silver nanoparticles. The UV–Vis maximum absorption at ~ 430 nm and fluorescence emission peaks at ~ 487 nm confirmed the presence of Ag NPs. Morphology and structural properties of Ag NPs and the effect of ultrasound studies revealed: (i) the formation of polydispersed and spherical particles with different sizes; (ii) size reduction and homogeneity increase by ultrasound treatment. Antibacterial activity of different concentrations of green synthesized Ag NPs has been assessed on Gram-negative S. typhimurium and Gram-positive S. aureus, revealing higher sensitivity on Gram-negative bacteria.

scholarly journals Characterization of Zinc oxide Nanostructures prepared by hydrothermal method with Antibacterial property

2019 ◽  
Vol 17 (42) ◽  
pp. 108-124
Author(s):  
Ibrahim Abdulkareem Ali
Keyword(s):  
Zinc Oxide ◽  
Antibacterial Activity ◽  
Crystallite Size ◽  
Annealing Temperature ◽  
Energy Gap ◽  
Antibacterial Property ◽  
Zno Nanostructures ◽  
Zinc Oxide Nanostructures ◽  
Oxide Nanostructures ◽  
Uv Visible

        In this study, Zinc oxide nanostructures were synthesized via a hydrothermal method by using zinc nitrate hexahydrate and sodium hydroxide as a precursor. Three different annealing temperatures were used to study their effect on ZnO NSs properties. The synthesized nanostructure was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Atomic force microscope (AFM), and Fourier Transform Infrared Spectroscopy (FTIR). Their optical properties were studied by using UV -visible spectroscopy. The XRD analysis confirms that all ZnO nanostructures have the hexagonal wurtzite structure with average crystallite size within the range of (30.59 - 34.52) nm. The crystallite size increased due to the incensement of annealing temperature. FESEM analysis indicates that ZnO has hexagonal shape of cylindrical pores, plate-like nanocrystals and Nanorods. AFM analysis shows that the average surface roughness of ZnO Nanostructures increases from 3.96 to 19.1 nm with the increase of annealing temperature. The FTIR peaks indicate successful preparation of ZnO Nanostructures. The FTIR method was used to analyses the chemical bonds which conformed the present of the Zn-O group in the region between (400-500) cm-1. The UV-visible showed a red shift in the absorption spectra related to the shift in the energy gap related to increase in the particle size.  the band gap energy has been calculated from the optical absorption spectra. The annealing process has been fond more effective on the value of energy gap. As the annealing temperature increases, the value of energy gap, increases as well; from (3.12to 3.22) eV. The prepared Nanostructure is used for antibacterial property. It shows strong antibacterial activity against S. aureus and P.aeuruginosa bacteria by the agar disc diffusion method. The white precipitate of ZnO NSs has superior antibacterial activity on gram-positive (S. aureus) than the gram-negative (P.aeuruginosa) bacteria.

scholarly journals INVESTIGATION ON PRE-TREATMENT PROCESS IN MICROCRYSTALLINE CELLULOSE (MCC) FROM OIL PALM EMPTY FRUIT BUNCH (EFB)

2018 ◽  
Vol 3 (1) ◽  
pp. 87-96
Author(s):  
Muhammad Arif Fahmi Supian ◽  
Khairatun Najwa Mohd Amin ◽  
Saidatul Shima Jamari ◽  
Shahril Mohamad
Keyword(s):  
Microcrystalline Cellulose ◽  
Morphological Characteristics ◽  
Alkaline Treatment ◽  
Empty Fruit Bunch ◽  
Characteristic Peak ◽  
Reinforcing Agent ◽  
Good Potential ◽  
The Mean ◽  
The Difference ◽  
Pre Treatment

In this study, microcrystalline cellulose (MCC) was extracted from empty fruit bunch (EFB) with alkaline treatment, bleaching and acid hydrolysis treatment and its properties were compared with commercial MCC. Two conditions were optimized in this study which are fiber consistency and sodium hydroxide (NaOH) concentration in alkaline pretreatment. The obtained optimum consistency and alkaline concentration are 5% and 20%respectively. The physicochemical and morphological characteristics, elemental composition and size distribution of the obtained alpha cellulose and MCC were analyzed in this work. Fourier transform infrared spectroscopy (FTIR) analysis provided clear evidence that the characteristic peak of lignin and hemicellulose were absent in the spectrum of the alpha cellulose and MCC. The difference in surface morphology and aggregation between alpha cellulose, MCC and commercialized MCC were observed by scanning electron microscopy (SEM). The mean length of approximately 251.3 μm, 41.4 μm and 138.6 μm were measured for alpha cellulose, MCC and commercialized MCC respectively. Thus, the isolated MCC from EFB has a good potential to be utilized as reinforcing agent in green composites and may be a precursor for future roselle derived nanocellulose, and thus a promising subject in nanocomposite research.

scholarly journals Antibacterial Activity of Partially Oxidized Ag/Au Nanoparticles against the Oral PathogenPorphyromonas gingivalisW83

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Megan S. Holden ◽  
Jason Black ◽  
Ainsely Lewis ◽  
Marie-Claire Boutrin ◽  
Elvin Walemba ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Periodontal Disease ◽  
Noble Metals ◽  
Bimetallic Nanoparticles ◽  
Periodontal Pocket ◽  
Dissolution Behavior ◽  
Galvanic Replacement ◽  
Chloroauric Acid ◽  
Ag Nps ◽  
Silver Dissolution

Advances in nanotechnology provide opportunities for the prevention and treatment of periodontal disease. While physicochemical properties of Ag containing nanoparticles (NPs) are known to influence the magnitude of their toxicity, it is thought that nanosilver can be made less toxic to eukaryotes by passivation of the NPs with a benign metal. Moreover, the addition of other noble metals to silver nanoparticles, in the alloy formulation, is known to alter the silver dissolution behavior. Thus, we synthesized glutathione capped Ag/Au alloy bimetallic nanoparticles (NPs)viathe galvanic replacement reaction between maltose coated Ag NPs and chloroauric acid (HAuCl4) in 5% aqueous triblock F127 copolymer solution. We then compared the antibacterial activity of the Ag/Au NPs to pure Ag NPs onPorphyromonas gingivalisW83, a key pathogen in the development of periodontal disease. Only partially oxidized glutathione capped Ag and Ag/Au (Au : Ag ≈ 0.2) NPs inhibited the planktonic growth ofP. gingivalisW83. This effect was enhanced in the presence of hydrogen peroxide, which simulates the oxidative stress environment in the periodontal pocket during chronic inflammation.

scholarly journals Cyathea gigantea (Cyatheaceae) as an antimicrobial agent against multidrug resistant organisms

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Kathakali Nath ◽  
Anupam Das Talukdar ◽  
Mrinal Kanti Bhattacharya ◽  
Deepshikha Bhowmik ◽  
Shiela Chetri ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antibacterial Property ◽  
Treatment Options ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Synergistic Activity ◽  
Gram Positive ◽  
Traditional Use ◽  
Gram Negative ◽  
Multidrug Resistant Organisms

Abstract Background Rapid emergence of multidrug resistant (MDR) organisms in hospital and community settings often result into treatment failure, thus leading the clinicians with fewer treatment options. Cyathea gigantea, an ethnomedicinally important fern used in cuts and wound infections. So, if this medicinal plant is used in treating the MDR infections then it might bring certain relief in future treatment options. Methods Antibacterial activity of C. gigantea against MDR bacteria was assed using well diffusion and broth microdilution methods to determine the diameters of growth inhibition zones, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Synergistic activity was also determined with the conventional antibiotics by disc diffusion method followed by FIC index of each of the tested antibiotic was calculated. The active extract was then subjected to fractionation by column chromatography and antibacterial activity was done with each of the collected fractions. Results Crude extract of C. gigantea was found to be active against all the tested organisms. The MIC was 200 μg/ml against Gram-positive i.e., Staphylococcus aureus ATCC 25923 and 400 μg/ml against Gram-negative i.e., Escherichia coli ATCC 25922 and Pseudomonas aeruginosa PAO1, while the MBC was 400 μg/ml in case of Gram-positive and 800 μg/ml for Gram-negative. The synergistic activity revealed that the plant extract increased the antibacterial property of the studied antibiotics and the FIC index showed that significant synergistic activity was shown by ciprofloxacin followed by tetracycline, ampicillin and oxacillin. Antibacterial activity with the fractionated extract showed that the FR II, FR III and FR IV were active against both Gram-positive and Gram-negative bacteria, whereas FR I, FR V and FR VI did not show antibacterial property against any of the tested bacteria. Conclusions Extracts of C. gigantea was found active against both selected Gram-positive and Gram-negative organisms and thus offers the scientific basis for the traditional use of the fern. The present study also provides the basis for future study to validate the possible use against multidrug resistant organisms.

The Effect of Modification of Hydroxyapatite Whisker with Zinc Acetate via Sol-Gel Technology

2013 ◽  
Vol 364 ◽  
pp. 655-659 ◽  
Author(s):  
Jian Feng Jin ◽  
Wen Ying Liu ◽  
Wen Yun Zhang ◽  
Qing Hua Chen ◽  
Yan Bo Yuan ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Antibacterial Activity ◽  
Zinc Acetate ◽  
Ph Value ◽  
Antibacterial Property ◽  
Sol Gel ◽  
Annealing Treatment ◽  
Sem Images ◽  
Different Shapes

Antibacterial activity of zinc oxide (ZnO) or strengthening of hydroxylapatite whisker (HAPw) had been studied and applied widely. However, antibacterial property of ZnO-HAPw was scarcely researched nowadays. The aim of this study was to further investigate several kinds of morphologies of ZnO-HAPw prepared by sol-gel technology at different pondus hydrogenii (pH) value and temperature. Four kinds of morphologies of ZnO-HAPw were granule, triangle, short rod and gongs nail at 70°C and pH=6.4, 37°C and pH=6.6, 70°C and pH=6.6, 70°C and pH=6.6. The SEM images of HAPw and ZnO-HAPw samples showed that the HAPw surface was smooth and no difference after annealing treatment. In addition, different shapes of nanoZnO fused uniformly on the HAPw surface. The EDS indicates nanoZnO fuses on HAPw surface.

Synthesis of antibacterial silver–chitosan-modified bionanocomposites by RAFT polymerization and chemical reduction methods

2016 ◽  
Vol 49 (2) ◽  
pp. 173-193 ◽  
Author(s):  
Mojtaba Abbasian ◽  
Farideh Mahmoodzadeh
Keyword(s):  
Antibacterial Activity ◽  
Hybrid Materials ◽  
Chemical Reduction ◽  
Proton Nuclear Magnetic Resonance ◽  
Diffusion Method ◽  
Infrared Spectrometry ◽  
Resonance Spectroscopy ◽  
Ag Nps ◽  
Stabilizing Agent ◽  
X Ray

Chitosan (Cts) was first modified with 4-cyano,4-[(phenylcarbothioyl)sulfanyl]pentanoic acid to serve as reversible addition–fragmentation chain transfer (RAFT) agent, and then the controlled grafting polymerizations of acrylic acid (PAA) were performed. The resultant copolymers were used as a stabilizing agent for preparation of colloidal silver nanoparticles (Ag NPs) in the range of 2–10 nm. Afterwards, montmorillonites (MMTs) were added to the solution of colloidal Ag NPs for improving thermal stability. Proton nuclear magnetic resonance spectroscopy, Fourier transform infrared spectrometry, energy dispersive X-ray spectroscopy, X-ray diffraction analysis, and scanning electron microscopy images demonstrate the successful synthesis of the graft copolymer. Their thermal behavior was examined by differential scanning calorimetry and thermogravimetric analyses.The antibacterial activity of Ag/Cts-g-PAA and Ag/Cts-g-PAA/MMT was investigated against Staphylococcus aureus, Escherichia coli, and Candida albicans by the disc diffusion method using Mueller Hinton agar. Antimicrobial tests show that Ag/Cts-g-PAA has much higher antimicrobial activity than Ag/Cts-g-PAA/MMT. This method would enable a wide variety of molecular designs to afford novel types of tailored hybrid materials composed of natural polysaccharides and synthetic polymers. The new hybrid materials were used as a stabilizing agent for preparation of Ag bionanocomposites with good antibacterial activity.

scholarly journals Green Synthesis and Antibacterial Activity of HAp@Ag Nanocomposite Using Centella asiatica (L.) Urban Extract and Eggshell

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Xuan Nui Pham ◽  
Hoa Thi Nguyen ◽  
Ngan Thi Pham
Keyword(s):  
Electron Microscopy ◽  
Antibacterial Activity ◽  
Green Synthesis ◽  
Antibacterial Properties ◽  
Centella Asiatica ◽  
Diffusion Method ◽  
Ag Nps ◽  
X Ray ◽  
Synthesis Of Nanoparticles ◽  
Green Approach

In recent years, the green synthesis of nanoparticles via biological processes has attracted considerable attention. Herein, we introduce a facile and green approach for the synthesis of poriferous silver nanoparticles (Ag-NPs) decorated hydroxylapatite (HAp@Ag) nanoparticles with excellent antibacterial properties. All the nanocomposites were fully characterized in the solid state via various techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectrometer (EDX), in which the synthesized Ag-NPs (24 nm in diameter) and their homogeneous incorporation on HAp have been studied by ultraviolet-visible (UV-vis) technique, transmission electron microscopy (TEM), and dynamic light scattering (DLS) analysis. The obtained results indicate that the structure and morphology of HAp have no significant changes after the incorporation of Ag-NPs on its surface. Moreover, an impressive antibacterial activity of HAp@Ag nanocomposite against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa has been recorded by using the agar well diffusion method. As a result, the HAp@Ag nanocomposite promises to be a great biomedical material with high antibacterial properties.

Antimicrobial Activity of O-Carboxymethyl Chitosan Nanofibers Containing Silver Nanoparticles Synthesized by Green Method

2016 ◽  
Vol 40 ◽  
pp. 136-145 ◽  
Author(s):  
Metwally Ezzat ◽  
Mohammed Ghanim ◽  
Hassan Nageh ◽  
Ahmed H. Hassanin ◽  
Ahmed Abdel-Moneim
Keyword(s):  
Antibacterial Activity ◽  
Wound Dressing ◽  
Pathogenic Bacteria ◽  
Reaction Times ◽  
Carboxymethyl Chitosan ◽  
Diffusion Method ◽  
Ag Nps ◽  
High Antibacterial Activity ◽  
Transmission Electron ◽  
Bacteria And Fungi

New green synthesis of Ag-nanoparticles (Ag-NPs) using O-Carboxymethyl Chitosan (O-CMCs) as stabilizing agent and ascorbic acid as reducing agent was achieved. The reaction was carried out in an autoclave at a pressure of 0.12 MPa and a temperature of 120°C at varying concentrations of solution precursors and different reaction times. The size, shape and structure of Ag-NPs were measured using transmission electron microscope (TEM), X-Ray Diffraction (XRD), FT-IR and UV spectrophotometers. The Ag-NPs stabilized in O-CMCs were blended with polyvinyl alcohol (PVA) polymer solution and then electrospun to produce wound dressing nanofibers with high antibacterial activity. The morphological study of O-CMCs/ PVA/Ag-NPs nanofiber membranes was characterized using SEM. Finally, the release behavior of Ag-NPs from these nanofibers was examined and the antibacterial activity was measured against some skin pathogenic bacteria and fungi using the agar diffusion method. The newly developed membranes show a unique antibacterial activity against the tested strains and were presented as promising active wound dressing materials in medical applications.

scholarly journals Toxicity of Nanoparticles againstDrosophila melanogaster(Diptera: Drosophilidae)

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Salah-Eddin A. Araj ◽  
Nida’ M. Salem ◽  
Ihab H. Ghabeish ◽  
Akl M. Awwad
Keyword(s):  
Silver Nanoparticles ◽  
Drosophila Melanogaster ◽  
Pest Management ◽  
Pest Control ◽  
Screening Program ◽  
Fruit Fly ◽  
Ag Nps ◽  
Leaf Extracts ◽  
Sulfur Nanoparticles ◽  
Nanoparticles Of Silver

In recent years, nanotechnology has become one of the most promising new approaches for pest control. In our screening program, laboratory trials were conducted to determine the effectiveness of five sources of silver nanoparticles (Ag NPs) and sulfur nanoparticles (S NPs) on larval, pupal, and adults of the fruit flyDrosophila melanogaster. Nanoparticles of silver and sulfur were synthesized through reducing, stabilizing, and capping plant leaf extracts method and different concentrations (10, 50, 100, 200 ppm) were tested onD. melanogaster. Results showed that silver nanoparticles (Ag NPs) were highly effective on larvae, pupae, and adults’ mortality and egg deterrence. On the contrary, none of the tested nanoparticles has a significant effect on pupae longevity. The results also showed that silver nanoparticles can be used as a valuable tool in pest management programs ofD. melanogaster.

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