Skin Regeneration Using Dermal Substrates that Contain Autologous Cells and Silver Nanoparticles to Promote Antibacterial Activity: In Vitro Studies

AbstractWe aimed to isolate Acinetobacter baumannii (A. baumannii) from wound infections, determine their resistance and virulence profile, and assess the impact of Silver nanoparticles (AgNPs) on the bacterial growth, virulence and biofilm-related gene expression. AgNPs were synthesized and characterized using TEM, XRD and FTIR spectroscopy. A. baumannii (n = 200) were isolated and identified. Resistance pattern was determined and virulence genes (afa/draBC, cnf1, cnf2, csgA, cvaC, fimH, fyuA, ibeA, iutA, kpsMT II, PAI, papC, PapG II, III, sfa/focDE and traT) were screened using PCR. Biofilm formation was evaluated using Microtiter plate method. Then, the antimicrobial activity of AgNPs was evaluated by the well-diffusion method, growth kinetics and MIC determination. Inhibition of biofilm formation and the ability to disperse biofilms in exposure to AgNPs were evaluated. The effect of AgNPs on the expression of virulence and biofilm-related genes (bap, OmpA, abaI, csuA/B, A1S_2091, A1S_1510, A1S_0690, A1S_0114) were estimated using QRT-PCR. In vitro infection model for analyzing the antibacterial activity of AgNPs was done using a co-culture infection model of A. baumannii with human fibroblast skin cell line HFF-1 or Vero cell lines. A. baumannii had high level of resistance to antibiotics. Most of the isolates harbored the fimH, afa/draBC, cnf1, csgA and cnf2, and the majority of A. baumannii produced strong biofilms. AgNPs inhibited the growth of A. baumannii efficiently with MIC ranging from 4 to 25 µg/ml. A. baumannii showed a reduced growth rate in the presence of AgNPs. The inhibitory activity and the anti-biofilm activity of AgNPs were more pronounced against the weak biofilm producers. Moreover, AgNPs decreased the expression of kpsMII , afa/draBC,bap, OmpA, and csuA/B genes. The in vitro infection model revealed a significant antibacterial activity of AgNPs against extracellular and intracellular A. baumannii. AgNPs highly interrupted bacterial multiplication and biofilm formation. AgNPs downregulated the transcription level of important virulence and biofilm-related genes. Our findings provide an additional step towards understanding the mechanisms by which sliver nanoparticles interfere with the microbial spread and persistence.

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The Design, Characterization and Antibacterial Activity of Heat and Silver Crosslinked Poly(Vinyl Alcohol) Hydrogel Forming Dressings Containing Silver Nanoparticles

Nanomaterials ◽

10.3390/nano11010096 ◽

2021 ◽

Vol 11 (1) ◽

pp. 96

Author(s):

John Jackson ◽

Helen Burt ◽

Dirk Lange ◽

In Whang ◽

Robin Evans ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Silver Nitrate ◽

Vinyl Alcohol ◽

Unmet Need ◽

Chemical Characterization ◽

Wound Dressings ◽

Poly Vinyl Alcohol ◽

Burn Wound

The prompt treatment of burn wounds is essential but can be challenging in remote parts of Africa, where burns from open fires are a constant hazard for children and suitable medical care may be far away. Consequently, there is an unmet need for an economical burn wound dressing with a sustained antimicrobial activity that might be manufactured locally at low cost. This study describes and characterizes the novel preparation of a silver nitrate-loaded/poly(vinyl alcohol) (PVA) film. Using controlled heating cycles, films may be crosslinked with in situ silver nanoparticle production using only a low heat oven and little technical expertise. Our research demonstrated that heat-curing of PVA/silver nitrate films converted the silver to nanoparticles. These films swelled in water to form a robust, wound-compatible hydrogel which exhibited controlled release of the antibacterial silver nanoparticles. An optimal formulation was obtained using 5% (w/w) silver nitrate in PVA membrane films that had been heated at 140 °C for 90 min. Physical and chemical characterization of such films was complemented by in vitro studies that confirmed the effective antibacterial activity of the released silver nanoparticles against both gram positive and negative bacteria. Overall, these findings provide economical and simple methods to manufacture stable, hydrogel forming wound dressings that release antibiotic silver over prolonged periods suitable for emergency use in remote locations.

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Fabrication of Silver Nanoparticles Supported on Rice Straw: In Vitro Antibacterial Activity and its Heterogeneous Catalysis in the Degradation of 4-Nitrophenol

BioResources ◽

10.15376/biores.11.2.3691-3708 ◽

2016 ◽

Vol 11 (2) ◽

Cited By ~ 4

Author(s):

Roshanak Khandanlou ◽

Gek Cheng Ngoh ◽

Wen Tong Chong ◽

Saadi Bayat ◽

Elnaz Saki

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Heterogeneous Catalysis ◽

Rice Straw ◽

In Vitro Antibacterial Activity

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PHYTOCHEMICAL SCREENING AND GAS CHROMATOGRAPHY-MASS SPECTROSCOPY ANALYSIS OF BIOACTIVE COMPOUNDS AND BIOSYNTHESIS OF SILVER NANOPARTICLES USING SPROUT EXTRACTS OF VIGNA RADIATA L. AND THEIR ANTIOXIDANT AND ANTIBACTERIAL ACTIVITY

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2019.v12i2.29253 ◽

2019 ◽

pp. 180-184

Author(s):

SIVAKUMAR T

Keyword(s):

Gas Chromatography ◽

Antioxidant Activity ◽

Silver Nanoparticles ◽

Antibacterial Activity ◽

Mass Spectroscopy ◽

Vigna Radiata ◽

Green Gram ◽

Hexadecanoic Acid ◽

Gas Chromatography Mass Spectroscopy

Objectives: The present study was aimed to investigate the facile synthesis of silver nanoparticles (AgNPs) using the green gram sprout extract (GGSE) of Vigna radiata L. and also in vitro studies of antioxidant and antimicrobial activities. Methods: Gas chromatography-mass spectroscopy techniques have been used for the qualitative and quantitative evaluation of the phytochemicals present in the green gram seedlings. The antioxidant activity of AgNPs and GGSE was analyzed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. In vitro antibacterial activity was performed using the agar well diffusion method. Results: The presence of various secondary metabolites such as flavonoids, steroids, terpenoids, alkaloids, amino acids, polyphenol, glycoside, and protein was found in samples. The major chemical compounds of V. radiata were n-hexadecanoic acid, stigmasterol, caffeine, hexadecanoic acid, cholest-5-en-3-ol (3.beta.)-, and cyclopentane. The percentage of DPPH activity was enhanced on increasing the concentration of AgNPs. In vitro antibacterial effect of the diverse concentrations of AgNPs was investigated against each Gram-negative (Klebsiella aerogenes, and Escherichia coli) and Gram-positive (Bacillus substilis and Staphylococcus aureus) bacterial strains. Conclusion: The result suggests that biosynthesized AgNPs have good antibacterial and antioxidant activity and might be a potential for the bioactive components.

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