Impact of chemical composition of ecotoxicological test media on the stability and aggregation status of silver nanoparticles

An endophytic strain of Streptomyces antimycoticus L-1 was isolated from healthy medicinal plant leaves of Mentha longifolia L. and used for the green synthesis of silver nanoparticles (Ag-NPs), through the use of secreted enzymes and proteins. UV–vis spectroscopy, Fourier-transform infrared (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and dynamic light scattering (DLS) analyses of the Ag-NPs were carried out. The XRD, TEM, and FT-IR analysis results demonstrated the successful biosynthesis of crystalline, spherical Ag-NPs with a particle size of 13–40 nm. Further, the stability of the Ag-NPs was assessed by detecting the surface Plasmon resonance (SPR) at 415 nm for one month or by measuring the NPs surface charge (−19.2 mV) by zeta potential analysis (ζ). The green-synthesized Ag-NPs exhibited broad-spectrum antibacterial activity at different concentrations (6.25–100 ppm) against the pathogens Staphylococcus aureus, Bacillus subtilis Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhimurium with a clear inhibition zone ranging from (9.5 ± 0.4) nm to (21.7 ± 1.0) mm. Furthermore, the green-synthesized Ag-NPs displayed high efficacy against the Caco-2 cancerous cell line (the half maximal inhibitory concentration (IC50) = 5.7 ± 0.2 ppm). With respect to antibacterial and in-vitro cytotoxicity analyses, the Ag-NPs concentration of 100 ppm was selected as a safe dose for loading onto cotton fabrics. The scanning electron microscopy connected with energy-dispersive X-ray spectroscopy (SEM-EDX) for the nano-finished fabrics showed the distribution of Ag-NPs as 2% of the total fabric elements. Moreover, the nano-finished fabrics exhibited more activity against pathogenic Gram-positive and Gram-negative bacteria, even after 10 washing cycles, indicating the stability of the treated fabrics.

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Stabilization of Silver Nanoparticles with a Dithiocarbamate Ligand and Formation of Nanocomposites by Combination with Polythiophene Derivative Nanoparticles

Advances in Condensed Matter Physics ◽

10.1155/2018/4376051 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Paris Jonathan Reynoso-García ◽

Marisol Güizado-Rodríguez ◽

Victor Barba ◽

Gabriel Ramos-Ortiz ◽

Hugo Martínez-Gutiérrez

Keyword(s):

Silver Nanoparticles ◽

Absorption Band ◽

Sodium Citrate ◽

Average Diameter ◽

Optoelectronic Device ◽

Ag Nps ◽

Spherical Morphology ◽

Dithiocarbamate Ligand ◽

The Stability ◽

Polythiophene Derivative

Spherical morphology for silver nanoparticles (Ag NPs) stabilized with dithiocarbamate (DTC) by reducing silver nitrate with sodium borohydride was obtained, while the addition of sodium citrate and hydrogen peroxide allowed the formation of silver nanotriangles (Ag NTs). Solutions of bright yellow and blue colors characteristic of both morphologies were observed. UV-vis optical analysis of NPs stabilized with DTC showed a plasmonic absorption band at 393 nm characteristic for spherical morphology, while two bands were observed at 332 nm and 762 nm, and a shoulder around 500 nm for the triangular morphology; with these spectra each morphology was confirmed. In these spectra an absorption band between 250 and 260 nm confirms the presence of DTC ligand. The stability of the NPs was achieved using an 8.69 × 10-3 mM solution of 4-(ethylaminodithiocarbamate) methylpyridine di-n-butyltin (IV) through a transmetallation reaction. Silver nanoparticles (Ag NPs) with spherical morphology of average diameter of 12.7 ± 1.2 nm and triangular morphology with 28.9 ± 0.8 nm for each side of the triangles were analyzed by high resolution scanning electron microscopy (HR-SEM). UV-vis spectra also showed the stability of NPs with DTC for more than three months. A copolymer derived of 3-hexylthiophene with (E)-2-(ethyl(4-((4-nitrophenyl) diazenyl) phenyl) amino) ethyl 2-(thiophen-3-yl) acetate (PA) was tested to get polymer NPs by reprecipitation method using THF/water systems. PA Polymer NPs having average diameter of 9.0 ± 1.7 nm were found. By quick and easy procedure, the formation of nanocomposite (NC) of spherical Ag NPs and PA polymer NPs was reached. This NC could be used as imaging agent, electrochemical biosensor, and photonic and optoelectronic device materials.

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Nanoencapsulation of Silver-Based Antimicrobial Drugs

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314083557 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C1644-C1644

Author(s):

Jacinthe Gagnon ◽

Rachel Caruso ◽

Katharina Fromm

Keyword(s):

Silver Nanoparticles ◽

Antimicrobial Agents ◽

Cell Attachment ◽

Alveolar Epithelial Cells ◽

Ag Nps ◽

Antimicrobial Drugs ◽

Alveolar Epithelial ◽

Low Cytotoxicity ◽

The Stability ◽

Silver Compounds

Implant-associated infections still remain an issue in medicine and can cause various medical complications. In order to ensure proper host-cell integration and biocompatibility to an implant, it is essential to prevent bacterial adhesion during the critical period of 6 hours after surgery. Moreover, as the implants are increasingly used in medicine, bacteria are becoming more resistant to antibiotics, in such a way that new developments in preventing and curing infections are more than ever needed. Silver compounds and nanoparticles are gaining more interest from the scientific society as a replacement to antibiotics. However, silver compounds may be too soluble and even toxic for the host. Encapsulation might be very advantageous in order to increase the stability and biocompatibility of silver drugs. In addition, it allows a more controllable release of antimicrobial agents. In this study, ceria nanocapsules with integrated silver nanoparticles (Ag/CeO2 NCs) were synthesized according to the method depicted in the figure below. The capsules were then characterized using XRD, TEM, SEM, and FT-IR. Silver nanoparticles (Ag NPs) are visible on the surface as well as in the cavity of Ag/CeO2 NCs, suggesting that they were integrated within the ceria shell. This system can release silver during a period exceeding 3 months, which demonstrates a good release control of the antimicrobial agent. The Ag/CeO2 NCs have a low cytotoxicity towards human alveolar epithelial cells, but allow only a poor cell attachment. In order to improve the cell attachment on the nanocapsules, as well as to reduce the silver being released, a TiO2 coating around the Ag/CeO2 NCs was added to this system. This resulted in the so-called Ag/CeO2/TiO2 NCs. These novel nanocontainers were also characterized in order to evaluate the cytotoxicity and antimicrobial activity.

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Green Synthesis, Characterization, Enzyme Inhibition, Antimicrobial Potential, and Cytotoxic Activity of Plant Mediated Silver Nanoparticle Using Ricinus communis Leaf and Root Extracts

Biomolecules ◽

10.3390/biom11020206 ◽

2021 ◽

Vol 11 (2) ◽

pp. 206

Author(s):

Anadil Gul ◽

Fozia ◽

Asmat Shaheen ◽

Ijaz Ahmad ◽

Baharullah Khattak ◽

...

Keyword(s):

Silver Nanoparticles ◽

Ricinus Communis ◽

Cost Effective ◽

Synthesis Process ◽

Ag Nps ◽

Tem Analysis ◽

Root Extracts ◽

Transmission Electron ◽

Mean Size ◽

The Stability

The need of non-toxic synthesis protocols for nanoparticles arises developing interest in biogenic approaches. The present project was focused on cost effective, environment congenial synthesis of Ag nanoparticles and their biological applications. Leaf and root extracts of Ricinus communis were used as a reducing and stabilizing agent in synthesis process. A Proposed mechanism in published literature suggested that Indole-3-acetic acid, l-valine, triethyl citrate, and quercetin-3-0-p-d-glucopyranoside phytoconstituents of Ricinus communis act as reducing and capping agents. The synthesized Ag NPs were characterized with a help X-ray diffractometer, Transmission electron microscopy, UV-Vis spectrophotometry and Fourier Transform Infrared Spectroscopy (FTIR). The XRD results inveterate the synthesis of pure nano size crystalline silver particles. The FTIR data revealed the possible functional groups of biomolecules involved in bio reduction and capping for efficient stabilization of silver nanoparticles. TEM analysis confirmed the almost spherical morphology of synthesized particles with mean size 29 and 38 nm for R-Ag-NPs (root) and L-Ag-NPs (leaf), respectively. The stability of synthesized nanoparticles was examined against heat and pH. It was observed that synthesized nanoparticles were stable up to 100 °C temperature and also showed stability in neutral, basic and slightly acidic medium (pH 05–06) for several months while below pH 5 were unstable. The synthesized silver nanoparticles had promising inhibition efficiency in multiple applications, including as bactericidal/fungicidal agents and Urease/Xanthine oxidase enzymes inhibitors. The cytotoxicity of synthesized nanoparticles shows that the concentration under 20 μg/mL were biologically compatible.

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Single-Step Green Synthesis of Highly Concentrated and Stable Colloidal Dispersion of Core-Shell Silver Nanoparticles and Their Antimicrobial and Ultra-High Catalytic Properties

Nanomaterials ◽

10.3390/nano11041007 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1007

Author(s):

Azam Ali ◽

Mariyam Sattar ◽

Fiaz Hussain ◽

Muhammad Humble Khalid Tareen ◽

Jiri Militky ◽

...

Keyword(s):

Silver Nanoparticles ◽

Green Synthesis ◽

Tannic Acid ◽

Rate Constant ◽

Catalytic Properties ◽

Colloidal Dispersion ◽

Alkaline Condition ◽

Core Shell ◽

Average Particle ◽

Ag Nps

The versatile one-pot green synthesis of a highly concentrated and stable colloidal dispersion of silver nanoparticles (Ag NPs) was carried out using the self-assembled tannic acid without using any other hazardous chemicals. Tannic acid (Plant-based polyphenol) was used as a reducing and stabilizing agent for silver nitrate in a mild alkaline condition. The synthesized Ag NPs were characterized for their concentration, capping, size distribution, and shape. The experimental results confirmed the successful synthesis of nearly spherical and highly concentrated (2281 ppm) Ag NPs, capped with poly-tannic acid (Ag NPs-PTA). The average particle size of Ag NPs-PTA was found to be 9.90 ± 1.60 nm. The colloidal dispersion of synthesized nanoparticles was observed to be stable for more than 15 months in the ambient environment (25 °C, 65% relative humidity). The synthesized AgNPs-PTA showed an effective antimicrobial activity against Staphylococcus Aureus (ZOI 3.0 mM) and Escherichia coli (ZOI 3.5 mM). Ag NPs-PTA also exhibited enhanced catalytic properties. It reduces 4-nitrophenol into 4-aminophenol in the presence of NaBH4 with a normalized rate constant (Knor = K/m) of 615.04 mL·s−1·mg−1. For comparison, bare Ag NPs show catalytic activity with a normalized rate constant of 139.78 mL·s−1·mg−1. Furthermore, AgNPs-PTA were stable for more than 15 months under ambient conditions. The ultra-high catalytic and good antimicrobial properties can be attributed to the fine size and good aqueous stability of Ag NPs-PTA. The unique core-shell structure and ease of synthesis render the synthesized nanoparticles superior to others, with potential for large-scale applications, especially in the field of catalysis and medical.

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Enhancement of multifunctional properties of leather surface decorated with silver nanoparticles (Ag NPs)

Journal of Molecular Structure ◽

10.1016/j.molstruc.2021.130130 ◽

2021 ◽

Vol 1234 ◽

pp. 130130

Author(s):

Hamed Elsayed ◽

Mohamed Hasanin ◽

Mohamed Rehan

Keyword(s):

Silver Nanoparticles ◽

Ag Nps ◽

Multifunctional Properties

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Antibacterial activity of royal jelly-mediated green synthesized silver nanoparticles

AMB Express ◽

10.1186/s13568-021-01213-9 ◽

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.

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Toxicity and chemical transformation of silver nanoparticles in A549 lung cells: dose-rate-dependent genotoxic impact

Environmental Science Nano ◽

10.1039/d0en00533a ◽

2021 ◽

Author(s):

Laure Bobyk ◽

Adeline Tarantini ◽

David Beal ◽

Giulia Veronesi ◽

Isabelle Kieffer ◽

...

Keyword(s):

Cell Cycle ◽

Silver Nanoparticles ◽

Dose Rate ◽

Cell Metabolism ◽

A549 Cells ◽

Dna Integrity ◽

Lung Cells ◽

Ag Nps ◽

Rate Dependent ◽

A549 Lung

Acute exposure of A549 cells to Ag-NPs induces stronger effects on DNA integrity, ROS level, cell metabolism and cell cycle than repeated exposure. Ag-NPs dissolves in both exposure conditions and Ag ions recombine with thiolated proteins.

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Green synthesis of silver nanoparticles: Characterization and its potential biomedical applications

Green Processing and Synthesis ◽

10.1515/gps-2021-0039 ◽

2021 ◽

Vol 10 (1) ◽

pp. 412-420

Author(s):

Mona S. Alwhibi ◽

Dina A. Soliman ◽

Manal A. Awad ◽

Asma B. Alangery ◽

Horiah Al Dehaish ◽

...

Keyword(s):

Silver Nanoparticles ◽

Aloe Vera ◽

Inhibition Zone ◽

Biologically Active ◽

Noble Metal Nanoparticles ◽

Biological Synthesis ◽

Ag Nps ◽

Mouse Melanoma ◽

Therapeutic Benefits ◽

Vis Spectroscopy

Abstract In recent times, research on the synthesis of noble metal nanoparticles (NPs) has developed rapidly and attracted considerable attention. The use of plant extracts is the preferred mode for the biological synthesis of NPs due to the presence of biologically active constituents. Aloe vera is a plant endowed with therapeutic benefits especially in skincare due to its unique curative properties. The present study focused on an environmental friendly and rapid method of phytosynthesis of silver nanoparticles (Ag-NPs) using A. vera gel extract as a reductant. The synthesized Ag-NPs were characterized by transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier transform infrared (FTIR), and dynamic light scattering (DLS). TEM micrographs showed spherical-shaped synthesized Ag-NPs with a diameter of 50–100 nm. The UV-Vis spectrum displayed a broad absorption peak of surface plasmon resonance (SPR) at 450 nm. The mean size and size distribution of the formed Ag-NPs were investigated using the DLS technique. Antibacterial studies revealed zones of inhibition by Ag-NPs of A. vera (9 and 7 mm) against Pseudomonas aeruginosa and Escherichia coli, respectively. Furthermore, the antifungal activity was screened, based on the diameter of the growth inhibition zone using the synthesized Ag-NPs for different fungal strains. Anticancer activity of the synthesized Ag-NPs against the mouse melanoma F10B16 cell line revealed 100% inhibition with Ag-NPs at a concentration of 100 µg mL−1. The phytosynthesized Ag-NPs demonstrated a marked antimicrobial activity and also exhibited a potent cytotoxic effect against mouse melanoma F10B16 cells. The key findings of this study indicate that synthesized Ag-NPs exhibit profound therapeutic activity and could be potentially ideal alternatives in medicinal applications.

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Size Control of Synthesized Silver Nanoparticles by Simultaneous Chemical Reduction and Laser Fragmentation in Origanum majorana Extract: Antibacterial Application

Materials ◽

10.3390/ma14092326 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2326

Author(s):

Entesar Ali Ganash ◽

Reem Mohammad Altuwirqi

Keyword(s):

Silver Nanoparticles ◽

Irradiation Time ◽

Chemical Reduction ◽

Size Control ◽

Reduction Process ◽

Laser Wavelength ◽

X Ray Diffraction ◽

Ag Nps ◽

Transmission Electron ◽

Origanum Majorana

In this work, silver nanoparticles (Ag NPs) were synthesized using a chemical reduction approach and a pulsed laser fragmentation in liquid (PLFL) technique, simultaneously. A laser wavelength of 532 nm was focused on the as produced Ag NPs, suspended in an Origanum majorana extract solution, with the aim of controlling their size. The effect of liquid medium concentration and irradiation time on the properties of the fabricated NPs was studied. While the X-ray diffraction (XRD) pattern confirmed the existence of Ag NPs, the UV–Vis spectrophotometry showed a significant absorption peak at about 420 nm, which is attributed to the characteristic surface plasmon resonance (SPR) peak of the obtained Ag NPs. By increasing the irradiation time and the Origanum majora extract concentration, the SPR peak shifted toward a shorter wavelength. This shift indicates a reduction in the NPs’ size. The effect of PLFL on size reduction was clearly revealed from the transmission electron microscopy images. The PLFL technique, depending on experimental parameters, reduced the size of the obtained Ag NPs to less than 10 nm. The mean zeta potential of the fabricated Ag NPs was found to be greater than −30 mV, signifying their stability. The Ag NPs were also found to effectively inhibit bacterial activity. The PLFL technique has proved to be a powerful method for controlling the size of NPs when it is simultaneously associated with a chemical reduction process.

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