Silver nanoparticles – wolves in sheep's clothing?

The available controlling agents for mosquito vectors are chemical insecticides and the frequent usage of these insecticides creating resistance among mosquito vectors and environmental pollutions. Thus, the study was designed to synthesize and characterize the Ag nanoparticles (AgNPs) through a methanol leaf extract of Ocimum canum and find the larvicidal prospective of the AgNPs on the 4th instar larvae of Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. The obtained outcomes show that the methanol leaf extract of O. canum was effectively reduced the silver ions and produce constant silver nanoparticles. It was characterized and confirmed by various scientific techniques such as UV-vis spectrum, XRD, SEM, FT-IR and EDaX. Various concentrations (10, 50, 150, 200, and 250 ppm) of characterized nanoparticles were tested for larvicidal activity. The premier larval death was observed at 24 h of treatment on A. aegypti with LC50= 17.03 ppm, followed by C. quinquefasciatus with LC50= 14.89 ppm of methanol extract of O. canum and no death was noticed on A. stephensi. The LD90 value for A. aegypti and C. quinquefasciatus were 24.18 & 20.65 ppm respectively. Hence, the Ag nanoparticles produced from methanol leaf extract of O. canum retains efficiency to control A. aegypti and C. quinquefasciatus. Thus, it might support partially to replace the chemical insecticide which used against these vectors and might contribute to reduce environmental pollution.

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Synthesis of Silver Nanoparticles from Malva parviflora Extract and Effect on Ecto-5'- Nucleotidase(5'-NT), ADA and AMPDA Enzymes in Sera of Patients with Arthrosclerosis

Baghdad Science Journal ◽

10.21123/bsj.14.4.742-750 ◽

2017 ◽

Vol 14 (4) ◽

pp. 742-750 ◽

Cited By ~ 1

Author(s):

Baghdad Science Journal

Keyword(s):

Silver Nanoparticles ◽

Silver Nanoparticle ◽

Silver Ions ◽

Reducing Agent ◽

Rapid Reduction ◽

Agno3 Solution ◽

Malva Parviflora

The present research included synthesis of silver nanoparticle from(1*10-3,1*10-4 and1*10-5) M aqueous AgNO3 solution through the extract of M.parviflora reducing agent. In the process of synthesizing silver nanoparticles we detected a rapid reduction of silver ions leading to the formation of stable crystalline silver nanoparticles in the solution.

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Antimicrobial Effect of Electrospun Nanofibers Loaded with Silver Nanoparticles: Influence of Ag Incorporation Method

Journal of Nanomaterials ◽

10.1155/2021/9920755 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Luis Jesús Villarreal-Gómez ◽

Graciela Lizeth Pérez-González ◽

Nina Bogdanchikova ◽

Alexey Pestryakov ◽

Vadim Nimaev ◽

...

Keyword(s):

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Silver Nanoparticle ◽

Electrospun Nanofibers ◽

Silver Ions ◽

Antimicrobial Effect ◽

The Other ◽

High Antimicrobial Activity ◽

Biomedical Industry ◽

Incorporation Method

The antimicrobial bioactivity of silver nanoparticles is well known, and they can be used widely in many applications, becoming especially important in the biomedical industry. On the other hand, the electrospun nanofibers possess properties that can enhance silver nanoparticle applicability. However, silver nanoparticle bioactivity differs depending on the loading of silver ions into electrospun nanofibers. This review is aimed at comparing different silver incorporation methods into electrospun nanofibers and their antimicrobial activity, discussing each procedure’s limitations, and presenting the most promising one. This review showed that the preferred techniques for incorporating silver nanoparticles were direct blending and ultraviolet irradiation methods due to their simplicity and efficient results. Besides, polyacrylonitrile nanofibers (PAN) have been the most reported system loaded with silver nanoparticles. Finally, independently of the technique used, silver nanoparticle-loaded nanofibers show high antimicrobial activity in all cases.

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Application of Gradient and Confocal Raman Spectroscopy to Analyze Silver Nanoparticle Diffusion in Medieval Glasses

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.8.89 ◽

2009 ◽

Vol 8 ◽

pp. 89-97 ◽

Cited By ~ 8

Author(s):

F. Rubio ◽

Sofia Pérez-Villar ◽

Miguel Angel Garrido ◽

Juan Rubio ◽

J.L. Oteo

Keyword(s):

Raman Spectroscopy ◽

Silver Nanoparticles ◽

Silver Nanoparticle ◽

Glass Surface ◽

Microprobe Analysis ◽

Glass Structure ◽

Silver Ions ◽

Nanoparticle Concentration ◽

Confocal Raman Spectroscopy ◽

Nanoparticle Diffusion

In this work it has been carried out the diffusion of silver ions in medieval glasses by a heat treatment process. Silver ions are transformed into both silver nanoparticles and nanoclusters after redox reactions with reducing glass ions. Changes in glass colour due to the formation of these silver nanoparticles have been analysed by means of visible spectroscopy. At the same time, changes in glass structure have been analysed by means of Raman scattering. By using confocal Raman spectroscopy the in deep glass structural changes occurring after silver ion diffusion and silver nanoparticle formation have been studied. These changes have been corroborated by means of gradient Raman spectroscopy where the silver ion and silver nanoparticle diffusion have been analysed on a fractured glass surface. In all cases have been observed that silver nanoparticles produce a depolymerisation of the glass structure and that such depolymerisation increases with the amount of silver nanoparticles. By using Microprobe Analysis it has been found that the higher silver nanoparticle concentration is on the glass surface and it decreases with the distance to the surface according to a diffusion process. By using nanoindentation measurements on original and gradient glass surfaces it has been found an increase of the Young modulus from 60 to 85 GPa, being the first value that corresponding to the glass surface with high silver nanoparticle concentration, and the second one for the glass without silver. This result is in accordance with Raman and Microprobe analysis.

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Effect of silver nanoparticles on biofilms of microorganisms (review)

Journal of New Medical Technologies eJournal ◽

10.12737/8117 ◽

2015 ◽

Vol 9 (1) ◽

pp. 0-0

Author(s):

Гладких ◽

P. Gladkikh

Keyword(s):

Silver Nanoparticles ◽

High Efficiency ◽

Antibacterial Properties ◽

Silver Ions ◽

Experimental Models ◽

Human Pathogens ◽

Antibiotic Resistant ◽

Medical Supplies ◽

Antibiotic Drugs

Nanotechnology enter in all spheres of human activity, particularly in medicine. Using nanoprogress allows the use of various nanostructures in the traditional methods therapy of various pathologies. The growing resistance to antibiotic drugs among human pathogens strains of microorganisms requires the development of alternatives. Silver nanoparticles are current contenders for the role of an alternative to modern antibiotics. They are able to transfer therapeutic agents, act on the membrane of microbial cells, disrupting their livelihoods and leading to death, as they are less toxic than silver ions. The use of nanoparticles is an effective tool in combating formed biofilms on medical supplies, and prevent to their education. Nanoparticles have proved positively against many antibiotic-resistant strains of microorganisms, including planktonic phase P. aureginosa. Synergistic effect observed while using of nanoparticles and various antibiotics. Antibacterial properties studied in experimental models of peritonitis and meningoencephalitis. In case of peritonitis high efficiency.

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Single Pot Synthesis of Gellan Gum Coated Silver Nanoparticles and its Antimicrobial Activity

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23295 ◽

2021 ◽

Vol 33 (9) ◽

pp. 2049-2052

Author(s):

D. Muralidharan ◽

A. Jaculin Raiza ◽

K. Pandian

Keyword(s):

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Silver Nanoparticle ◽

Silver Ions ◽

Reducing Agent ◽

Gellan Gum ◽

Pathogenic Microorganisms ◽

Complete Reduction ◽

Excellent Activity ◽

Analytical Tools

A single pot synthesis of gellan gum coated silver nanoparticles using aniline as a reducing agent has been investigated in present study. The reaction was facile at 80 ºC under reflux condition and the complete reduction of silver ions was noted within 2 h. The resulting gellan gum protected silver nanoparticle was isolated and analyzed with various analytical tools. The antimicrobial activity of the prepared nanocomposite had shown an excellent activity against some selected pathogenic microorganisms.

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Hydrothermal Assisted Biogenic Synthesis of Silver Nanoparticles And Their Anticandidal Activity On Virulent Candida Isolates From COVID-19 Patients

10.21203/rs.3.rs-1203202/v1 ◽

2021 ◽

Author(s):

Fatma O Khalil ◽

Enas M. Ghonaim ◽

Shimaa Abed El-sattar ◽

Sally W. Elkhadry ◽

Hala El-Refai ◽

...

Keyword(s):

Silver Nanoparticles ◽

Fourier Transforms ◽

Silver Ions ◽

Thymus Vulgaris ◽

Remarkable Change ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Anticandidal Activity

Abstract Till now the exact mechanism and effect of biogenic silver nanoparticles on fungus is an indefinable question. To focus on this issue, we prepared hydrothermal assisted thyme coated silver nanoparticles (T/AgNPs) and their toxic effect on Candida isolates is described. The role of thyme (Thymus Vulgaris) in the reduction of silver ions and stabilization of T/AgNPs are estimated by Fourier transforms infrared spectroscopy, structure and size of present silver nanoparticles were detected via atomic force microscopy as well as high-resolution transmission electron microscopy. The biological activity of T/AgNPs was observed against Candida isolates from COVID-19 Patients. Testing of virulence of Candida species using Multiplex PCR. T/AgNPs proved highly effective against Candida albicans, Candida kruzei, Candida glabrata and MIC values ranging from 156.25 to 1,250 µg/mL and MFC values ranging from 312.5 to 5,000 µg/mL. The structural and morphological modifications due to T/AgNPs on Candida albicans were detected by TEM. It was highly observed that when Candida albicans cells were subjected to 50 and 100 µg/mL T/AgNPs, a remarkable change in the cell wall and cell membrane was observed.

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Growth of Ag-Nanoparticles: Shape-Directing Role of Silver Ions and Stabilizer in Aqueous Solutions

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v6i3.2642 ◽

2010 ◽

Vol 6 (3) ◽

pp. 1049-1058

Author(s):

Zoya Zaheer ◽

Rafiuddin Rafiuddin

Keyword(s):

Silver Nanoparticles ◽

Optical Properties ◽

Ag Nanoparticles ◽

Cetyltrimethylammonium Bromide ◽

Silver Ions ◽

Average Diameter ◽

Capping Agent ◽

Transmission Electron ◽

Uv Visible

Silver nanoparticles were synthesized using Tulsi leaves extract as reducing as well as a capping agent to reduce the steps and parameters involved in the synthesis. The morphology, stability and optical properties of Ag-nanoparticles depend on reactants and stabilizer, cetyltrimethylammonium bromide (CTAB) concentrations. The silver nanoparticles were characterized by UV-visible spectrophotometer, and transmission electron microscope (TEM). Spherical morphology of the silver nanoparticles with an average diameter of 25 nm. Morphology changed markedly from spherical aggregated to highly polydispersed in presence of CTAB.

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