scholarly journals Hyaluronic Acid Derivative Molecular Weight-Dependent Synthesis and Antimicrobial Effect of Hybrid Silver Nanoparticles

2021 ◽  
Vol 22 (24) ◽  
pp. 13428
Author(s):  
Guillem Ferreres ◽  
Sílvia Pérez-Rafael ◽  
Juan Torrent-Burgués ◽  
Tzanko Tzanov
Keyword(s):  
Molecular Weight ◽  
Silver Nanoparticles ◽  
Hyaluronic Acid ◽  
Mammalian Cells ◽  
Antimicrobial Effect ◽  
Mechanistic Study ◽  
Ag Nps ◽  
Antimicrobial Function ◽  
Reduced Toxicity

Silver nanoparticles (Ag NPs) appeared as promising antimicrobial candidates to face the development of antibiotic resistance. Although reported as toxic towards mammalian cells, their combination with biomolecules have shown reduced toxicity, while maintaining the antimicrobial function. Herein, hyaluronic acid (HA) with low (40 kDa), medium (200 and 600 kDa) and high (2 MDa) molecular weight (Mw) was modified with adipic acid dihydrazide (ADH) and used as reducing and capping agents to synthesise antimicrobial hybrid Ag NPs. The Mw of the polymer played a crucial role in the morphology, size and antibacterial activity of the Ag NPs. The 600 and 200 kDa HA-ADH-Ag NPs were able to reduce the Escherichia coli and Staphylococcus aureus concentration by more than 3 logs, while the 40 kDa NPs reached ~2 logs reduction. The 2 MDa HA-ADH failed to form homogenous NPs with strong bactericidal activity. A mechanistic study of the interaction with a model bacterial membrane using Langmuir isotherms confirmed the greater interaction between bacteria and higher Mw polymers and the effect of the NP’s morphology. The nanocomposites low toxicity to human skin cells was demonstrated in vitro, showing more than 90% cell viability after incubation with the NPs.

Silver nanoparticles used to counter Monilinia fructicola fungicide-resistance and reduce fungicide environmental footprint 

2021 ◽  
Author(s):  
Constantinos Chrysikopoulos ◽  
Anastasios A. Malandrakis ◽  
Nektarios Kavroulakis ◽  
Anthi Stefanarou
Keyword(s):  
Silver Nanoparticles ◽  
Control Plant ◽  
Resistance Mutation ◽  
Silver Ions ◽  
Apple Fruit ◽  
Ag Nps ◽  
Gene Target ◽  
Benzimidazole Fungicides

<div><span>The potential of silver nanoparticles (Ag-NPs) to control plant pathogen <em>Monilia</em><em>fructicola </em>and to deter environmental contamination by reducing fungicide doses was evaluated <em>in vitro </em>and <em>in vivo. </em> </span>F<span>ungitoxicity screening </span>of <em><span>M. fructicola </span></em><span>isolates resulted in the detection of 18 benzimidazole-resistant (BEN-R) isolates with reduced sensitivity to fungicides  thiophanate methyl (TM)  and carbendazim. All resistant isolates caried the E198A resistance mutation in their </span><em><span>β</span>-</em>tubulin gene, target site of the benzimidazole fungicides. <span>Ag-NPs could effectively control both sensitive (BEN-S) and resistant isolates while the combination of Ag-NPs with TM significantly enhanced their fungitoxic effect both <em>in vitro </em>and in apple fruit tests. The positive correlation observed between Ag-NPs and TM+Ag-NPs treatments indicates a mixture-enhanced Ag-NPs activity/availability as a possible mechanism of synergy. No correlation between Ag-NPs  and AgNO<sub>3 </sub>could  be found suggesting difference(s) in the fungitoxic mechanism of action between Nps and their bulk/ionic counterparts. Indications of the involvement of energy (ATP) metabolism in the mode of action of Ag-NPs were also evident by the synergy observed between Ag-NPs and the </span>oxidative phosphorylation<span>-uncoupler fluazinam (FM) against both BEN-R and BEN-S phenotypes. The role of silver ions release on the inhibitory action of Ag-NPs against the fungusis probably limited since the AgNPs/NaCl combination enhanced fungitoxicity, a fact that could not be justified by the expected binding of silver with chlorine ions. Concluding, Ag-NPs can be effectively used as a means of controlling both BEN-S and BEN-R <em>M. </em><em>fructicola </em>isolates </span>while <span>their combination with conventional fungicides should aid anti-resistant strategies and reduce the environmental impact of synthetic fungicides by reducing effective doses to the control the pathogen.</span></div>

scholarly journals Enhancing the biocompatibility of siliconepolycarbonate urethane based implant materials

2019 ◽  
Vol 5 (1) ◽  
pp. 453-455 ◽  
Author(s):  
Kiriaki Athanasopulu ◽  
Larysa Kutuzova ◽  
Joana Thiel ◽  
Günter Lorenz ◽  
Ralf Kemkemer
Keyword(s):  
Molecular Weight ◽  
Cell Proliferation ◽  
Hyaluronic Acid ◽  
Cell Growth ◽  
Block Copolymers ◽  
Cytotoxic Potential ◽  
Implant Surface ◽  
Characterization Methods ◽  
Hard Segments

AbstractPolyurethane-bases block copolymers (TPCUs) are block-copolymers with systematically varied soft and hard segments. They have been suggested to serve as material for chondral implants in joint regeneration. Such applications may require the adhesion of chondrocytes to the implant surface, facilitating cell growth while keeping their phenotype. Thus, aims of this work were (i) to modify the surface of soft biostable polyurethane-based model implants (TPCU and TSiPCU) with high-molecular weight hyaluronic acid (HA) using an optimized multistep strategy of immobilization, and (ii) to evaluate bioactivity of the modified TPCUs in vitro. Our results show no cytotoxic potential of the TPCUs. HAbioactive molecules (Mw =700kDa) were immobilized onto the polyurethane surface via polyethylenimine (PEI) spacers, and modifications were confirmed by several characterization methods. Tests with porcine chondrocytes indicated the potential of the TPCU-HA for inducing enhanced cell proliferation.

scholarly journals Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of Essential Oils from AgNPs and AuNPs Elicited Lavandula angustifolia In Vitro Cultures

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 606 ◽  
Author(s):  
Aneta Wesołowska ◽  
Paula Jadczak ◽  
Danuta Kulpa ◽  
Włodzimierz Przewodowski
Keyword(s):  
Molecular Weight ◽  
Silver Nanoparticles ◽  
Essential Oils ◽  
Culture Media ◽  
In Vitro Cultures ◽  
Gas Chromatography Mass Spectrometry ◽  
Lavandula Angustifolia ◽  
Gold And Silver Nanoparticles ◽  
The Media

The aim of this study was to determine how the addition of gold and silver nanoparticles to culture media affects the composition of essential oils extracted from Lavandula angustifolia propagated on MS media with the addition of 10 and 50 mg·dm−3 of gold (24.2 ± 2.4 nm) and silver (27.5 ± 4.8 nm) nanocolloids. The oil extracted from the lavender tissues propagated on the medium with 10 mg·dm−3 AgNPs (silver nanoparticles) differed the most with respect to the control; oil-10 compounds were not found at all, and 13 others were detected which were not present in the control oil. The addition of AuNPs (gold nanoparticles) and AgNPs to the media resulted in a decrease of lower molecular weight compounds (e.g., α- and β-pinene, camphene, δ-3-carene, p-cymene, 1,8-cineole, trans-pinocarveol, camphoriborneol), which were replaced by those of a higher molecular weight (τ- and α-cadinol 9-cedranone, cadalene, α-bisabolol, cis-14-nor-muurol-5-en-4-one, (E,E)-farnesol).

scholarly journals Synthesis and biochemical characterization of silver nanoparticles grafted chitosan (Chi-Ag-NPs): in vitro studies on antioxidant and antibacterial applications

2020 ◽  
Vol 2 (4) ◽  
Author(s):  
Pavan Kumar Dara ◽  
R. Mahadevan ◽  
P. A. Digita ◽  
S. Visnuvinayagam ◽  
Lekshmi R. G. Kumar ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Biochemical Characterization ◽  
In Vitro Studies ◽  
Ag Nps

scholarly journals Size-Dependent Toxicity of Silver Nanoparticles to Bacteria, Yeast, Algae, Crustaceans and Mammalian Cells In Vitro

PLoS ONE ◽  
2014 ◽  
Vol 9 (7) ◽  
pp. e102108 ◽  
Author(s):  
Angela Ivask ◽  
Imbi Kurvet ◽  
Kaja Kasemets ◽  
Irina Blinova ◽  
Villem Aruoja ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Mammalian Cells ◽  
Size Dependent

scholarly journals Silver nanoparticles induce the cardiomyogenic differentiation of bone marrow derived mesenchymal stem cells via telomere length extension

2021 ◽  
Vol 12 ◽  
pp. 786-797
Author(s):  
Khosro Adibkia ◽  
Ali Ehsani ◽  
Asma Jodaei ◽  
Ezzatollah Fathi ◽  
Raheleh Farahzadi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Stem Cells ◽  
Bone Marrow ◽  
Silver Nanoparticles ◽  
Mesenchymal Stem Cells ◽  
Telomere Length ◽  
Cardiac Markers ◽  
Ag Nps ◽  
Cardiomyogenic Differentiation

Finding new strategies for the treatment of heart failures using stem cells has attracted a lot of attention. Meanwhile, nanotechnology-based approaches to regenerative medicine hypothesize a possible combination of stem cells and nanotechnology in the treatment of diseases. This study aims to investigate the in vitro effect of silver nanoparticles (Ag-NPs) on the cardiomyogenic differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs) through detection of cardiac markers. For this purpose, MSCs were isolated from bone marrow resident and differentiated to the cardiac cells using a dedicated medium with Ag-NPs. Also, the cardiomyogenic differentiation of BM-MSCs was confirmed using immunocytochemistry. Then, real-time PCR and western blotting assay were used for measuring absolute telomere length (TL) measurement, and gene and protein assessment of the cells, respectively. It was found that 2.5 µg/mL Ag-NPs caused elongation of the telomeres and altered VEGF, C-TnI, VWF, SMA, GATA-4, TERT, and cyclin D protein and gene expression in the cardiomyogenically differentiated BM-MSCs. Also, there was a significant increase in the protein and gene expression of Wnt3 and β-catenin as main components of pathways. We concluded that Ag-NPs could change the in vitro expression of cardiac markers of BM-MSCs via the Wnt3/β-catenin signaling pathway.

scholarly journals Silver Nanoparticles: Green Synthesis, Characterization, Blood Compatibility and Protoscolicidal Efficacy against Echinococcus granulosus

2021 ◽  
Vol 41 (03) ◽  
pp. 393-399
Author(s):  
Parwin Jalal Jalil
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silver Nanoparticles ◽  
Echinococcus Granulosus ◽  
Blood Compatibility ◽  
Ag Nps ◽  
X Ray ◽  
Hydatid Fluid ◽  
Scanning Electron

Spillage of protoscoleces within hydatid fluid during surgery for hydatid cyst is the main reason for its recurrence. Therefore, to inactivate the protoscoleces, various scolicidal substances have been tested. However, novel and more efficient agents are needed owing to several associated complications. This study focused on the effects of green synthetic Silver Nanoparticles (AgNPs) from Zizyphus spina- christi leaves on Echinococcus granulosus protoscoleces. Also, to evaluate the blood compatibility of Ag NPs. The Ag NPs were identified by ultraviolet-visible (UV-Visible) spectrophotometer, X-ray diffraction (XRD), Scanning electron microscopy imaging, and Energy-dispersive X-ray spectroscopy (EDX). Hydatid fluid was aspirated aseptically from cysts of infected sheep liver. The protoscoleces were exposed to Ag NPs at several concentrations. Also, scanning electron microscopy for ultrastructural changes and in vitro erythrocytes lysis was performed. The Ag NPs were spherical; the particles' size reached 50 nm, and presented a surface plasmon peak around 460 nm. The current study's findings indicated the powerful in vitro scolicidal efficacy of the green biosynthesized AgNPs. Several morphological alterations were observed on the protoscoleces by optical and scanning electron microscopy. Lysis of RBCs at different doses of Ag NPs was significantly (P≤0.05) less than the positive control value, thus proposing its biocompatibility. This work suggests that chemicals like polyphenols present in the extract of Z. spina- christi act as reducing and stabilizers agents to create Ag NPs Nevertheless, further investigations are needed to investigate the Ag NPs scolicidial effects in animal models.

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