Microwave Mediated Fast Synthesis of Silver Nanoparticles and Investigation of Their Antibacterial Activities for Gram-Positive and Gram-Negative Microorganisms

Herein, a simple one-step microwave irradiation technique has been used to synthesize the silver nanoparticles using silver nitrate (AgNO3) solution and cetyltrimethyl ammonium bromide (CTAB) as a stabilizing agent. The crystals of as-prepared nanoparticles were studied using X-ray diffraction (XRD) and a selected area electron diffraction (SAED) pattern, confirming the single-phase face-centered cubic structure. The optical property measured using UV-Vis spectroscopy shows an absorption maximum at 420 nm, which also confirms the formation of silver nanoparticles. Transmission electron microscopy (TEM) analysis revealed that the silver nanoparticles have a spherical shape with an average diameter of ~6 nm. The antibacterial properties of silver nanoparticles were investigated using both Gram-positive and Gram-negative microorganisms, such as Staphylococcus aureus, Pseudomonas aeruginosa, andEscherichia coli. Klebsiella pneumoniae, and Candida albicans. Results showed a highest zone of inhibition of about 35 mm against P. aeruginosa as compared with E. coli (21 mm), S. aureus (30 mm), K. pneumonia (28 mm), and C. albicans (29 mm). These studies suggested that silver nanoparticles prepared by this fast and effective method might be developed as antibacterial agents against an extensive range of microorganisms to control and stop the spreading and persistence of bacterial infections.

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Green Synthesis of Silver Nanoparticles using the Leaves Extract of Filicium decipiens and its Anti- Microbial Activity

Journal of Environmental Nanotechnology ◽

10.13074/jent.2021.09.213442 ◽

2021 ◽

Vol 10 (3) ◽

pp. 16-24

Author(s):

Sherin Monichan ◽

P. Mosae Selvakumar ◽

Christine Thevamithra ◽

M. S. A. Muthukumar Nadar ◽

Jesse Joel

Keyword(s):

Silver Nanoparticles ◽

Green Synthesis ◽

Average Diameter ◽

Diffusion Method ◽

Face Centered Cubic ◽

Gram Positive ◽

Gram Negative ◽

Vis Spectroscopy ◽

Face Centered ◽

Almost All

Silver nanoparticles has been used since ages, even till now it is exploited in almost all areas like medicine, textiles, industries, cosmetics, purification, dying and many more. There are many approaches which are used to synthesize silver nanoparticles. However, these approaches are either harmful to the environment or very costly. Therefore, green synthesis of silver nanoparticles (AgNPs) using leaves of Filicium decipiens eco-friendly and a very reliable method to procure AgNPs. Characterization of synthesized AgNPs were then done using UV-Vis spectroscopy and fluorescence which confirmed the formation of AgNPs, scanning electron microscope (SEM)confirmed its shape to be round and X-ray diffraction (XRD) determined its crystalline nature as face centered cubic structure. Furthermore, Dynamic Light Scattering (DLS) was also done in order to know the average diameter and zeta potential of AgNPs. However, it did not show potential results due to the aggregates formed during the green synthesis of AgNPs. In addition to this, anti-microbial test against bacteria such as gram negative (Escherichia. Coli) and gram positive (Bacillus.spc) were done using well-diffusion method and also its application of antimicrobial activity was tested over fabric to understand its application in textile industries. In both the cases, AgNPs showed more efficiency in gram negative bacteria than gram- positive.

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Bacterial Mediated Rapid and Facile Synthesis of Silver Nanoparticles and Their Antimicrobial Efficacy against Pathogenic Microorganisms

Materials ◽

10.3390/ma14102615 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2615

Author(s):

Md. Amdadul Huq ◽

Shahina Akter

Keyword(s):

Electron Microscopy ◽

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Field Emission ◽

Spherical Shape ◽

Xrd Analysis ◽

Gram Positive ◽

Tem Analysis ◽

Gram Negative ◽

X Ray

In the present study, silver nanoparticles (AgNPs), biosynthesized using culture supernatant of bacterial strain Paenarthrobacter nicotinovorans MAHUQ-43, were characterized and their antimicrobial activity was investigated against both Gram-positive Bacillus cereus and Gram-negative bacteria Pseudomonas aeruginosa. Bacterial-mediated synthesized AgNPs were characterized by UV-Visible (UV-Vis) spectrophotometer, field emission-transmission electron microscopy (FE-TEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) analysis. The UV-Vis spectral analysis showed the absorption maxima at 466 nm which assured the synthesis of AgNPs. The FE-TEM analysis revealed the spherical shape of nanoparticles with the size range from 13 to 27 nm. The EDX and XRD analysis ensured the crystalline nature of biosynthesized AgNPs. The FTIR analysis revealed the involvement of different biomolecules for the synthesis of AgNPs as reducing and capping agents. The bacterial-mediated synthesized AgNPs inhibited the growth of pathogenic strains B. cereus and P. aeruginosa and developed a clear zone of inhibition (ZOI). The MIC and MBC for both pathogens were 12.5 µg/mL and 25 µg/mL, respectively. Moreover, field emission scanning electron microscopy analysis revealed that the synthesized AgNPs can destroy the outer membrane and alter the cell morphology of treated pathogens, leading to the death of cells. This study concludes the eco-friendly, facile and rapid synthesis of AgNPs using P. nicotinovorans MAHUQ-43 and synthesized AgNPs showed excellent antimicrobial activity against both Gram-positive and Gram-negative pathogens.

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Phyllanthus reticulatus mediated synthesis and characterization of silver nanoparticles and its antibacterial activity against gram positive and gram negative pathogens

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v10i4.1603 ◽

2019 ◽

Vol 10 (4) ◽

pp. 3099-3106 ◽

Cited By ~ 1

Author(s):

Gomathi M ◽

Prakasam A ◽

Rajkumar P.V ◽

Rajeshkumar S ◽

Chandrasekaran R ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Leaf Extract ◽

Antibacterial Properties ◽

Spherical Shape ◽

Morphological Properties ◽

Gram Positive ◽

Gram Negative ◽

Sem Image ◽

Structural Surface

In this study, silver nanoparticles were successfully synthesized by using Phyllanthus reticulatus leaf extract at different concentration (5, 10, 15 mL). The prepared samples were analyzed their optical, structural, surface morphological properties, and along with these properties, the antibacterial properties were analyzed. The UV-vis absorption spectra show SPR band around 450 nm, shift to lower wavelength due to increasing extract concentration. This shift can be ascribing to a decrease in particle size. The crystallinity nature of the prepared samples is observed by the XRD profile; the calculated particles size by Scherrer’s formula displays a decrease in size with respect to leaf extract volume. From the SEM image, it can be seen that irregular and large size particles prepared at 5-10 mL and the smooth spherical shape and tiny particles were observed in the sample prepared at 15 mL. The small and spherical shape nanoparticles show good antibacterial activity against gram positive and negative bacterial pathogens. The activity of large and irregular shape particles may be due to the release of Ag+ ions and generation of ROS. Because of cell wall difference in bacteria, the better activity is observed against gram negative bacteria.

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Green synthesised silver nanoparticles incorporated electrospun poly(methyl methacrylate) nanofibers with different architectures for ophthalmologic alternatives

Journal of Bioactive and Compatible Polymers ◽

10.1177/0883911521997856 ◽

2021 ◽

Vol 36 (2) ◽

pp. 93-110

Author(s):

Princy Philip ◽

Tomlal Jose ◽

Sarath KS ◽

Sunny Kuriakose

Keyword(s):

Silver Nanoparticles ◽

Methyl Methacrylate ◽

Antibacterial Properties ◽

Analytical Techniques ◽

Morphological Properties ◽

Gram Positive ◽

Gram Negative ◽

Poly Methyl Methacrylate ◽

Antimicrobial Studies ◽

Eye Problems

Silver nanoparticles with 5–10 nm diameters are synthesised using Couroupita guianensis flower extract. The synthesised silver nanoparticles found to show good antimicrobial activity against gram negative and gram positive bacteria. Poly(methyl methacrylate) nanofibers with pristine, surface roughened and coaxial hollow forms are prepared by electrospinning. The structural and morphological properties of these pure and structurally modified poly(methyl methacrylate) nanofibers are evidenced by various analytical techniques. The antimicrobial studies of poly(methyl methacrylate) nanofibers having different architectures incorporated with silver nanoparticles are carried out. It is found that, all the three forms of poly(methyl methacrylate) nanofibers incorporated with silver nanoparticles show antibacterial properties against both gram positive and gram negative bacteria. Among these, surface roughened poly(methyl methacrylate) nanofibers incorporated with silver nanoparticles show highest antibacterial activity than the other two structural forms. The present study offers an alternative to the existing optical lenses. People especially those who suffer from eye problems can protect their eyes in a better way from infectious agents by wearing optical lens made from C. guianensis stabilised silver nanoparticles incorporated poly(methyl methacrylate) nanofibers than that made from pure poly(methyl methacrylate) nanofibers or films.

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Biosynthesis of CeO2 Nanoparticles Using Egg White and Their Antibacterial and Antibiofilm Properties on Clinical Isolates

Crystals ◽

10.3390/cryst11060584 ◽

2021 ◽

Vol 11 (6) ◽

pp. 584

Author(s):

Shalendra Kumar ◽

Faheem Ahmed ◽

Nagih M. Shaalan ◽

Osama Saber

Keyword(s):

Bacterial Infections ◽

Antibacterial Properties ◽

Spherical Shape ◽

Inhibition Zone ◽

Egg White ◽

Ceo2 Nanoparticles ◽

Inorganic Materials ◽

Ambient Conditions ◽

Uniform Size ◽

Tem Analysis

Bio-inspired synthesis is a novel and attractive environmentally friendly route to generating inorganic materials. In this work, the preparation of CeO2 NPs using egg white and investigation of their antibacterial properties both in liquid and solid growth medium against Escherichia coli and Staphylococcus aureus bacteria were reported. The CeO2 nanoparticles were characterized using X-ray diffraction (XRD), Field emission transmission electron microscope (FETEM), UV-Vis, Raman, and antibacterial measurements. The results from XRD and TEM analysis showed that the prepared nanoparticles were a single phase in the nano regime (5–7 nm) with spherical shape and uniform size distribution. Optical properties reflected the characteristics peaks of CeO2 in the UV-Vis range with a bandgap ~2.80 eV. The antibacterial activity of the synthesized NPs was achieved under ambient conditions with different bacteria and the results showed that the properties were different for both the bacteria. The highest activity with an inhibition zone of about 22 mm against S. aureus was obtained as compared with the 19 mm zone of inhibition obtained with E.coli. This finding will be of major significance that indicates a possibility to develop CeO2 NPs as antibacterial agents against extensive microorganisms to control and prevent the spread and persistence of bacterial infections.

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Bio fabrication of silver nanoparticles with antibacterial and cytotoxic abilities using lichens

Scientific Reports ◽

10.1038/s41598-020-73683-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mona A. Alqahtani ◽

Monerah R. Al Othman ◽

Afrah E. Mohammed

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Synergistic Effect ◽

Cancer Cell ◽

Spherical Particles ◽

Diffusion Method ◽

Gram Positive ◽

Gram Negative ◽

Vis Spectroscopy ◽

Hct 116

Abstract Recently, increase bacterial resistance to antimicrobial compounds issue constitutes a real threat to human health. One of the useful materials for bacterial control is Silver nanoparticles (AgNPs). Researchers tend to use biogenic agents to synthesize stable and safe AgNPs. The principal aim of this study was to investigate the ability of lichen in AgNPs formation and to find out their suppression ability to MDR bacteria as well as their cytotoxic activity. In the current study, lichens (Xanthoria parietina, Flavopunctelia flaventior) were collected from the south of the Kingdom of Saudi Arabia. Lichens methanolic extracts were used for conversion of Ag ions to AgNPs. Prepared biogenic AgNPs were characterized by Ultraviolet–Visible (UV–Vis) Spectroscopy, Transmission electron microscopy (TEM), Dynamic Light Scattering (DLS) and Zeta potential and Energy-Dispersive X-ray Spectroscopy (EDS). Lichens Secondary metabolites were determined by Fourier-Transform Infrared Spectroscopy (FTIR) and Gas Chromatography–Mass Spectrometry (GC–MS). The antibacterial activity and synergistic effect of AgNPs were evaluated against pathogenic bacteria, including gram-positive; Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin-resistant Enterococcus (VRE), and gram-negative; (Pseudomonas aeruginosa, Escherichia coli) as well as the reference strains (ATCC) using the agar disk diffusion method. Cytotoxic effect of biogenic AgNPs was tested against HCT 116 (Human Colorectal Cancer cell), MDA-MB-231 (Breast cancer cell), and FaDu (Pharynx cancer cell) by MTT test. TEM imaging showed well-dispersed spherical particles of 1–40 nm size as well as zeta size showed 69–145 nm. Furthermore, FTIR and GC–MS identified various lichen chemical molecules. On the other hand, the highest antibacterial activity of AgNPs was noticed against P. aeruginosa, followed by MRSA, VRE, and E. coli. AgNPs influence on gram-negative bacteria was greater than that on gram-positive bacteria and their synergistic effect with some antibiotics was noted against examined microbes. Moreover, higher cytotoxicity for biogenic AgNPs against FaDu and HCT 116 cell line in relation to MDA-MB-231 was noted. Given the current findings, the biogenic AgNPs mediated by lichens had positive antibacterial, synergistic and cytotoxic powers. Therefore, they might be considered as a promising candidate to combat the multi-drug resistance organisms and some cancer cells.

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Plasmon Resonance of Silver Nanoparticles as a Method of Increasing Their Antibacterial Action

Antibiotics ◽

10.3390/antibiotics7030080 ◽

2018 ◽

Vol 7 (3) ◽

pp. 80 ◽

Cited By ~ 10

Author(s):

Alexander Vasil’kov ◽

Ruslan Dovnar ◽

Siarhei Smotryn ◽

Nikolai Iaskevich ◽

Alexander Naumkin

Keyword(s):

Staphylococcus Aureus ◽

Silver Nanoparticles ◽

Plasmon Resonance ◽

Photoelectron Spectroscopy ◽

Antibacterial Properties ◽

Petri Dish ◽

Aureus Strain ◽

Gram Positive ◽

Gram Negative ◽

X Ray

In this article, a series of silver-containing dressings are prepared by metal-vapor synthesis (MVS), and their antibacterial properties are investigated. The antibacterial activity of the dressings containing silver nanoparticles (AgNPs) against some Gram-positive, and Gram-negative microorganisms (Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Moraxella spp.) has been determined. Based on the plasmon resonance frequency of these nanoparticles, the frequency of laser irradiation of the dressing was chosen. The gauze bandage examined showed pronounced antibacterial properties, especially to Staphylococcus aureus strain. When 470 nm laser radiation, with a power of 5 mW, was applied for 5 min, 4 h after inoculating the Petri dish, and placing a bandage containing silver nanoparticles on it, the antibacterial effect of the latter significantly increased—both against Gram-positive and Gram-negative microorganisms. The structure and chemical composition of the silver-containing nanocomposite were studied by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS). The synthesized AgNPs demonstrate narrow and monomodal particle size distribution with an average size of 1.75 nm. Atoms of metal in Ag/bandage system are mainly in Ag0 state, and the oxidized atoms are in the form of Ag-Ag-O groups.

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SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SILVER NANOPARTICLES STABILIZED BY CITRATE ANIONS

Proceedings of the Shevchenko Scientific Society. Series Сhemical Sciences ◽

10.37827/ntsh.chem.2020.60.127 ◽

2020 ◽

Vol 2020 (60) ◽

pp. 127-135

Author(s):

Liliya BAZYLYAK ◽

◽

Andriy KYTSYA ◽

Ilona KARPENKO ◽

Olena KARPENKO ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Cell Walls ◽

Colloidal Silver ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Vis Spectroscopy

Widespread use of synthetic antimicrobial drugs leads to the development of antibiotic resistance of pathogenic strains of microorganisms. Therefore, today researchers are very interested in drugs based on nanoparticles of metals, in particular silver and copper, which have antibacterial, antifungal and antiviral activity. One of the reasons for the high interest of researchers in AgNPs as an antimicrobial agent is the significantly lower toxicity of AgNPs compared to Ag+ ions. High antibacterial efficiency of silver nano¬particles is achieved due to their developed surface, which provides maximum contact with the environment. In addition, such nanoparticles are quite small and are able to penetrate cell membranes, to affect intracellular processes from within. Therefore, the aim of this work was to obtain concentrated colloidal silver solutions stabilized by citrate anions, which simultaneously provide satisfactory stabilization of colloidal silver solutions and are non-toxic, as well as to investigate the antimicrobial action of synthesized AgNPs. The solution of citrate stabilized silver nanoparticles (AgNPs) have been obtained via the reaction of reduction of silver nitrate by hydrazine in alkaline medium in the presence of sodium citrate. AgNPs were investigated using transmission electron microscopy (TEM) and UV-vis spectroscopy and the particles size and particles size distribution (PSD) were determined. It was observed that obtained AgNPs are mainly spherical shape. It was found that the mean diameter and PSD of AgNPs determined using TEM and UV-vis spectroscopy are close and equal to 14 and 5 nm and 15 and 4 nm respectively. Obtained solution was concentrated by evaporation at 70 C under reduced pressure up to achievement of AgNPs concentration equal to 200 mg/L. On the base of comparison of optical properties of initial silver sol and concentrated solution the minority of agglomeration of AgNPs was statement. At the same time AgNO3 test showed no change of UV-vis spectrum of concentrate that points on the absence of reducing agent in the solution; this fact indicate that hydrazine was eliminated from during the evaporation of initial AgNPs solution and obtained concentrate did not consist the toxic impurities. Antimicrobial activity of obtained citrate stabilised AgNPs against Gram-positive Bacillus subtilis and Gram-negative Escherichia coli bacterium was tested using disk diffusion method. It was found that AgNPs shown significant bactericidal effect even at low (25 mg/L) concentration as well as some higher efficiency against Gram-negative bacterium. There was also a slightly higher antimicrobial activity of the drug against gram-negative bacteria Escherichia coli compared with gram-positive bacteria Bacillus subtilis, due to the different structure of cell walls. In particular, the walls of gram-positive bacteria consist mainly of peptidoglycan (murein), and gram-negative bacteria have cell walls with a layer of peptidoglycan and an outer membrane with a lipopolysaccharide component, which is not present in gram-positive bacteria. Based on the studies, it can be concluded that the proposed method of synthesis of AgNPs is suitable for obtaining highly concentrated silver sols. This method of synthesis is simple in hardware design, scalable, and the resulting colloidal solutions are stable and do not contain harmful impurities. Therefore, due to the high antibacterial activity of citrate-anion-stabilized AgNPs against certain types of gram-positive and gram-negative bacteria, it can be recommended for the manufacture of bactericidal drugs for biomedical purposes.

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Facile synthesis of silver nanoparticles using Averrhoa bilimbi L and Plum extracts and investigation on the synergistic bioactivity using in vitro models

Green Processing and Synthesis ◽

10.1515/gps-2019-0058 ◽

2019 ◽

Vol 8 (1) ◽

pp. 873-884 ◽

Cited By ~ 3

Author(s):

Suresh Sagadevan ◽

Selvaraj Vennila ◽

Preeti Singh ◽

Jayasingh Anita Lett ◽

Mohd Rafie Johan ◽

...

Keyword(s):

Escherichia Coli ◽

Silver Nanoparticles ◽

Salmonella Typhi ◽

In Vitro Models ◽

Diffusion Method ◽

Gram Positive ◽

Gram Negative ◽

Vis Spectroscopy ◽

Test Cultures

Abstract The bacterial communities (Gram-negative and Gram-positive) form the biofilms which oppose the mode of action of antibiotics and affecting the immune system of the human. These chronic infections related to biofilm are always hard to be cured because of their inherent resistance to both antimicrobial agents and host defense. The present study is devoted to the synthesis of silver nanoparticles (AgNPs) using aqueous extracts of Averrhoa bilimbi leaf and Plum fruit (Prunus bokharensis) and its inhibitory effect on Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi. Here, AgNPs) were successfully prepared by green synthesis method obtained by the reduction of silver nitrate into silver ions. The synthesized AgNPs were characterized by UV-Vis Spectroscopy, XRD, FTIR, FESEM-EDAX and DLS analysis. The antimicrobial effects of the two extract were evaluated by the disk diffusion method. The green synthesized AgNPs exhibited good antibacterial activity against both Gram-negative and Gram-positive. They were also analyzed for their significant antibacterial activities against all the test cultures exposed whereas Escherichia coli and Salmonella typhi topped among other test cultures. The anti-proliferative activity of phytochemical mediated synthesis of Ag NPs was investigated for their cytotoxicity in Vero and Human epidermoid larynx carcinoma cell lines (HEp-2) based on their viability using MTT assay. The present study also represents the synergistic bioactivity of silver nanoparticles using in vitro models.

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Synthesis, characterization and biomedical applications of silver nanoparticles

Biomedicine ◽

10.51248/.v41i2.1058 ◽

2021 ◽

Vol 41 (2) ◽

pp. 458-464

Author(s):

Sabah Saad Abdulsahib

Keyword(s):

Silver Nanoparticles ◽

Ag Nanoparticles ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Potent Effect ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Prepared Nanoparticles ◽

Vis Spectroscopy ◽

Bacterial Action

Introduction and Aim:Silver nanoparticles (AgNPs) have been extensively useful in biomedical applications.This study aims to synthesize silver nanoparticles by lasers ablation and to use them as an anti-bacterial and anti-cancer agent. Materials and Methods:According to the current study, Ag-nanoparticles can be synthesized easily using pulsed laser ablation on a 99.81% pure silver target immersed in deionized water. The prepared nanoparticles werecharacteredbyUV-vis spectroscopy and X-ray diffraction (XRD), transmission electron microscopy (TEM), and atomic force microscopy (AFM) technique.Using a well-diffusion process, the anti-bacterial action of the synthesized Ag nanoparticles was tested versus two Gram-positive bacteria species (S. aureus and S. pyogenes) and two species of Gram-negative bacteria (E. coli and P. aeruginosa).The anticancer activity of the silver nanoparticles was evaluated by the MTT assay. Results:The generated AgNps had a maximum absorbance peak of 400 nm. The XRD analysis verified that the synthesized silver nanoparticles had been nanocrystalline. The AgNPsdid not affect any of the blood parameters. Gram-negative bacteria are more affected by silver than Gram-positive bacteria. The Ag nanoparticles had been shown a maximum anti-bacterial action at a concentration of 80 µg/mland had a lower effect with 20 µg/ml concentration while their efficacy at 40 and 60 µg/ml concentrationsappeared to be variable against all bacterial species.The findings show that AgNPshavea cytotoxic influence on cancer cellsin 80 ?g/ml concentration. Conclusion:In comparison to Gram-positive bacteria, silver nanoparticles show high antibacterial activity against Gram-negative bacteria. The prepared nanoparticles have a potent effect on cancer cells and restricted harmful effects on RBCs.

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