Cytotoxicity, cell uptake and microscopic analysis of titanium dioxide and silver nanoparticles in vitro

Abstract Due to continued technological development, people increasingly come in contact with engineered nanomaterials (ENMs) that are now used in foods and many industrial applications. Many ENMs have historically been shown to possess antimicrobial properties, which has sparked concern for how dietary nanomaterials impact gastrointestinal health via microbial dysbiosis. We employed an in vitro Human Gut Simulator system to examine interactions of dietary nano titanium dioxide (TiO2) with human gut microbiota. Electron microscopy indicated a close association of TiO2 particles with bacterial cells. Addition of TiO2 to microbial communities led to a modest reduction in community density but had no impact on community diversity and evenness. In contrast, administration of known antimicrobial silver nanoparticles (NPs) in a control experiment resulted in a drastic reduction of population density. In both cases, communities recovered once the addition of nanomaterials was ceased. Constrained ordination analysis of community profiles revealed that simulated colonic region was the primary determinant of microbiota composition. Accordingly, predicted community functional capacity and measured production of short-chain fatty acids were not changed significantly upon microbiota exposure to TiO2. We conclude that tested TiO2 NPs have limited direct effect on human gut microbiota.

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Silver Nanoparticles Embedded in Natural Rubber Films: Synthesis, Characterization, and Evaluation ofIn VitroToxicity

Journal of Nanomaterials ◽

10.1155/2016/2368630 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Caroline S. Danna ◽

Dalita G. S. M. Cavalcante ◽

Andressa S. Gomes ◽

Leandra E. Kerche-Silva ◽

Eidi Yoshihara ◽

...

Keyword(s):

Silver Nanoparticles ◽

Natural Rubber ◽

Chinese Hamster ◽

Cell Lineage ◽

Microscopic Analysis ◽

Visible Spectrum ◽

Electron Microscopic ◽

Force Microscopy ◽

Atomic Force

Natural rubber (NR) films can reduce silver metal ions forming embedded metal nanoparticles, a process that could be described as green synthesis. The NR films acting as a reactor generate and incorporate silver nanoparticles (AgNPs). Organic acids and amino acids play a crucial role in the formation of AgNPs. The plasmon extinction obtained in the UV-visible spectrum shows the presence of nanoparticles in the film after dipping the NR film into a solution of silver nitrate at 80°C. Electron microscopic analysis confirms the presence of AgNPs in the NR film and characterization by atomic force microscopy shows a change in the roughness of the NR film with AgNPs. In addition, our preliminary results fromin vitrotoxicity studies (MTT and comet assays) of the NR films and NR films with silver nanoparticles (NR/Ag) show that they are not toxic to cell lineage CHO-K1 (cells from the ovary of a Chinese hamster), an important result for potential medical applications.

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Addition of Silver Nanoparticles to Composite Resin: Effect on Physical and Bactericidal Properties In Vitro

Brazilian Dental Journal ◽

10.1590/0103-6440201302398 ◽

2014 ◽

Vol 25 (2) ◽

pp. 141-145 ◽

Cited By ~ 18

Author(s):

Patrícia Bolzan Agnelli das Neves ◽

José Augusto Marcondes Agnelli ◽

Cristina Kurachi ◽

Clovis Wesley Oliveira de Souza

Keyword(s):

Silver Nanoparticles ◽

Microscopic Analysis ◽

Control Group ◽

Biofilm Growth ◽

Force Microscopy ◽

Atomic Force ◽

Viable Cells ◽

Bactericidal Properties ◽

Sucrose Medium

The objectives of this study were to evaluate physical properties and antibacterial activity of a light-activated composite modified with silver nanoparticles. Discs were produced with unmodified resin (control group - CG) and modified resin with silver nanoparticles at two concentrations, 0.3% wt (MR03) and 0.6% wt (MR06). Streptococcus mutans and Lactobacillus acidophilus biofilms were induced in vitro by incubation of discs in a 20% sucrose medium, followed by sonication and counting of viable cells after 1, 4 and 7 days (n=9). The arithmetic roughness of all three groups was evaluated by atomic force microscopy (n=9). Compression assay was conducted in all groups to measure the compressive strength at failure and elasticity modulus (n=5). Data were subjected to ANOVA and Tukey's tests (α=0.05%). At all three time points the number of viable cells was statistically lower for MR03 and MR06 compared with CG, for both specimens. MR03 and MR06 showed no significant differences. Microscopic analysis demonstrated no significant differences for roughness among the three groups (p>0.05). The MR03 was stronger to compression than CG, and MR06 was statistically lower than CG and MR03. It was concluded that the MR03 were less conducive to biofilm growth, without compromising the strength in compression and surface roughness.

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Green synthesis and antibacterial activity of silver nanoparticles from the aqueous extracts of Cassia alata

Letters in Applied NanoBioScience ◽

10.33263/lianbs92.10371041 ◽

2020 ◽

Vol 9 (2) ◽

pp. 1037-1041

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Microscopic Analysis ◽

Inhibitory Effect ◽

Aqueous Extracts ◽

Minimum Concentration ◽

Cassia Alata ◽

Protein Leakage ◽

Ft Ir

The current study involves the synthesis of silver nanoparticles from the aqueous extracts of Cassia alata. The synthesized silver nanoparticles were characterized by UV-Vis, FT-IR, SEM-EDX and XRD. The in vitro bioactivity studies were examined against a Gram-positive and Gram-negative micro-organism by performing antibacterial activity, minimum inhibition assay, swarming motility and protein leakage assay. The characteristic study on the nanoparticles using spectrometric and microscopic analysis, revealed them to be sized between 25 nm and 60 nm. The nanoparticles on evaluating the antibacterial activity against Pseudomonas aeruginosa and Bacillus subtilis interacted well with the microorganisms producing a significant inhibitory effect at a minimum concentration of 0.5 µg/mL. The permeability of the particles was also studied through protein leakage assay.

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Caco-2 in vitro model of human gastrointestinal tract for studying the absorption of titanium dioxide and silver nanoparticles from seafood

Talanta ◽

10.1016/j.talanta.2021.122494 ◽

2021 ◽

pp. 122494

Author(s):

María Vanesa Taboada-López ◽

Baltazar Hiram Leal-Martínez ◽

Raquel Domínguez-González ◽

Pilar Bermejo-Barrera ◽

Pablo Taboada-Antelo ◽

...

Keyword(s):

Silver Nanoparticles ◽

Titanium Dioxide ◽

Gastrointestinal Tract ◽

In Vitro Model ◽

Human Gastrointestinal Tract ◽

Vitro Model

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Detection of intracellular silver nanoparticles using flow cytometry

ZHurnal «Patologicheskaia fiziologiia i eksperimental`naia terapiia» ◽

10.25557/0031-2991.2018.04.223-226 ◽

2018 ◽

pp. 223-226

Author(s):

С.И. Каба ◽

А.А. Соколовская

Keyword(s):

Flow Cytometry ◽

Silver Nanoparticles ◽

Endothelial Cells ◽

Silver Nanoparticle ◽

Cell Uptake ◽

Control Samples

Продемонстрировано обнаружение наночастиц серебра во внутриклеточном пространстве с помощью проточной цитофлуориметрии. В эндотелиальных клетках линии EA.hy926, инкубированных в растворе, содержащем 2 мкг/мл наносеребра, измеряли боковое светорассеяние. По сравнению с контрольными образцами этот параметр возрастал, в то время как прочие значимые характеристики не изменялись. Это подтверждает чувствительность метода к изменившемуся состоянию клеток и указывает на поглощение наночастиц серебра клетками при концентрации ниже токсической. The study demonstrated a possibility for detection of intracellular silver nanoparticles using flow cytometry. The parameter used in this work, side scattering, was measured in EA.hy926 endothelial cells incubated in a 2 mg/ml silver nanoparticle solution. This parameter was increased compared to control samples. Therefore, this technique was sensitive to changes in the cell status and suggested the cell uptake of the particles under the subtoxic conditions.

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