scholarly journals Selective localization of titanium dioxide nanoparticles at the interface and its effect on the impact toughness of poly(L-lactide)/poly(ether)urethane blends

2013 ◽  
Vol 7 (3) ◽  
pp. 261-271 ◽  
Author(s):  
H. Xiu ◽  
H. W. Bai ◽  
C. M. Huang ◽  
C. L. Xu ◽  
X. Y. Li ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Impact Toughness ◽  
Titanium Dioxide Nanoparticles ◽  
Selective Localization ◽  
The Impact

scholarly journals Effect of Titanium Dioxide Nanoparticles on the Expression of Efflux Pump and Quorum-Sensing Genes in MDR Pseudomonas aeruginosa Isolates

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 625
Author(s):  
Fatma Y. Ahmed ◽  
Usama Farghaly Aly ◽  
Rehab Mahmoud Abd El-Baky ◽  
Nancy G. F. M. Waly
Keyword(s):  
Titanium Dioxide ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Efflux Pumps ◽  
Antibiofilm Activity ◽  
The Impact

Most of the infections caused by multi-drug resistant (MDR) P. aeruginosa strains are extremely difficult to be treated with conventional antibiotics. Biofilm formation and efflux pumps are recognized as the major antibiotic resistance mechanisms in MDR P. aeruginosa. Biofilm formation by P. aeruginosa depends mainly on the cell-to-cell communication quorum-sensing (QS) systems. Titanium dioxide nanoparticles (TDN) have been used as antimicrobial agents against several microorganisms but have not been reported as an anti-QS agent. This study aims to evaluate the impact of titanium dioxide nanoparticles (TDN) on QS and efflux pump genes expression in MDR P. aeruginosa isolates. The antimicrobial susceptibility of 25 P. aeruginosa isolates were performed by Kirby–Bauer disc diffusion. Titanium dioxide nanoparticles (TDN) were prepared by the sol gel method and characterized by different techniques (DLS, HR-TEM, XRD, and FTIR). The expression of efflux pumps in the MDR isolates was detected by the determination of MICs of different antibiotics in the presence and absence of carbonyl cyanide m-chlorophenylhydrazone (CCCP). Biofilm formation and the antibiofilm activity of TDN were determined using the tissue culture plate method. The effects of TDN on the expression of QS genes and efflux pump genes were tested using real-time polymerase chain reaction (RT-PCR). The average size of the TDNs was 64.77 nm. It was found that TDN showed a significant reduction in biofilm formation (96%) and represented superior antibacterial activity against P. aeruginosa strains in comparison to titanium dioxide powder. In addition, the use of TDN alone or in combination with antibiotics resulted in significant downregulation of the efflux pump genes (MexY, MexB, MexA) and QS-regulated genes (lasR, lasI, rhll, rhlR, pqsA, pqsR) in comparison to the untreated isolate. TDN can increase the therapeutic efficacy of traditional antibiotics by affecting efflux pump expression and quorum-sensing genes controlling biofilm production.

scholarly journals Impact of Titanium Dioxide Nanoparticles on Cd Phytotoxicity and Bioaccumulation in Rice (Oryza sativa L.)

2020 ◽  
Vol 17 (9) ◽  
pp. 2979 ◽  
Author(s):  
Wei Zhang ◽  
Jinghua Long ◽  
Jianmin Geng ◽  
Jie Li ◽  
Zhongyi Wei
Keyword(s):  
Titanium Dioxide ◽  
Oryza Sativa ◽  
Plant Height ◽  
Oryza Sativa L ◽  
Titanium Dioxide Nanoparticles ◽  
Engineered Nanoparticles ◽  
Control Treatment ◽  
Booting Stage ◽  
Tio2 Nps ◽  
The Impact

The impact of engineered nanoparticles (ENPs) on the migration and toxicity of coexisting pollutants is still unclear, especially in soil media. This study aims to evaluate the impact of titanium dioxide nanoparticles (TiO2 NPs) on the phytotoxicity of cadmium (Cd) to Oryza sativa L., and the migration of cadmium (Cd) in the soil-rice system. Three different Cd stress groups (C1 group: 1.0 mg kg−1, C2 group: 2.5 mg kg−1 and C3 group: 5.0 mg kg−1) were set in the pot experiment, and the target concentration of TiO2 NPs in each group were 0 mg kg−1 (T0), 50 mg kg−1 (T1), 100 mg kg−1 (T2) and 500 mg kg−1 (T3). Plant height and biomass decreased with the increasing of Cd content in paddy soil. TiO2 NPs could lower the phytotoxicity of Cd in terms of the changes in the morphological and biochemical characteristics, especially in the tillering and booting stage. In the tillering stage, TiO2 NPs addition caused a significant increase in plant height, biomass and the total chlorophyll content in the leaves of Oryza saliva L. In the booting stage, TiO2 NPs addition caused a 15% to 32% and 24% to 48% reduction of malondialdehyde (MDA) content for the C2 and C3 group, respectively, compared to that of the respective control treatment (T0). TiO2-NPs addition reduced the activity of peroxidase (POD) in the leaves in the booting and heading stage, and the activity of catalase (CAT) in the tillering stage. In the C1 and C2 group, the grain Cd content in the 100 and 500 mg kg−1 TiO2 NPs treatments reached 0.47–0.84 mg kg−1, obviously higher than that of the treatment without TiO2 NPs (0.27–0.32 mg kg−1), suggesting that TiO2-NPs could promote Cd migration in the soil-rice system.

scholarly journals Effect of nanoparticles on Escherichia coli growth dynamics

2019 ◽  
pp. 107-113
Author(s):  
Laith B Alhusseini
Keyword(s):  
Escherichia Coli ◽  
Titanium Dioxide ◽  
Urinary Tract ◽  
Iron Oxide ◽  
Titanium Dioxide Nanoparticles ◽  
Growth Dynamics ◽  
Inhibition Zone ◽  
E Coli ◽  
Tract Infections ◽  
The Impact

Background: Nanoparticles (iron oxide and titanium dioxide nanoparticles) are another kind of critical materials that are produced for use in various research and different purposes. The bacteriology field being so critical seek to the intrinsic understanding on the effect of nanoparticles on bacterial growth and functions. Our investigation was planned to detect the impact of iron oxide (Fe3O4), titanium dioxide (TiO2) nanoparticles on growth of Escherichia coli (Iraqi isolate). Methods: Fifty urine samples of patients, who are suffering Urinary Tract Infections (UTIs) in Iraqi hospitals, were collected. Our study was included three parts: the 1st part was isolated and diagnosed the bacteria that cause the urinary tract infection, the 2nd part was sensitivity to antibiotics, and the 3rd has used the nanomaterials and study their impacts on the growth of E. col isolates. Result: The results showed that 30 E. coli isolates depending on the properties of biochemical and molecular detect. Five common types of antibiotics were examined for the treatment of infections of the urinary tract. Most E. coli were resistant to antibiotics, the ratios of ampicillin, amikacin and augmentin found to be 90%, 82% and 80% respectively. It concluded that bacteria were sensitive to imipenem and meropenem of about 50 %. So, the effect of iron oxide and titanium dioxide nanoparticles were studied for the growth of bacteria using the agar. The effectiveness against bacteria (diameters of the inhibition zone rate) found to be 18 mm for the 1st substance and 21 mm for 2nd substance. Conclusion: Our current study indicates that there is an effect of nanoparticles at the cellular level that can be used for beneficial biological application such as antibacterial. Keywords: Escherichia coli; Inhibition zone; Antibiotics; Nanoparticles

scholarly journals Impact of foliar application of nano micronutrient fertilizers and titanium dioxide nanoparticles on the growth and yield components of barley under supplemental irrigation

2016 ◽  
Vol 107 (2) ◽  
pp. 265 ◽  
Author(s):  
Mohsen JANMOHAMMADI ◽  
Tahereh AMANZADEH ◽  
Naser SABAGHNIA ◽  
Shahryar DASHTI
Keyword(s):  
Titanium Dioxide ◽  
Grain Yield ◽  
Chlorophyll Content ◽  
Foliar Application ◽  
Titanium Dioxide Nanoparticles ◽  
Foliar Spray ◽  
Growth And Yield ◽  
Nano Scale ◽  
The Impact ◽  
Semi Arid

Nano-fertilizers are new generation of the synthetic<em> </em>fertilizers which contain readily available nutrients in nano scale range. Nano fertilizers are preferred largely due to their efficiency and environment friendly nature compared to conventional<em> </em>chemical<em> </em>fertilizers. To evaluate the effects of foliar spray<em> </em>of micronutrient nano-fertilizer (iron and zinc) and nano-titanium dioxide (nTiO<sub>2</sub>) solution on grain yield and its components in barley under supplemental<em> </em>irrigation conditions, a field experiment was carried out in the semi-arid highland region of Maragheh, Iran. Barley plants were separately treated with of chelated nano-scale zinc oxide (ZnO) and ferric oxide (Fe<sub>2</sub>O<sub>3</sub>) suspensions during tillering stage, booting and milky stages. Results revealed that days to<em> </em>anthesis and maturity significantly increased after application of both nano-fertilizers. Furthermore<em>,</em> a considerable improvement was observed in grain mass, spike length, number of the grains per spike, chlorophyll content, grain yield and harvest index by application of nano-fertilizer. However the impact of nano zinc fertilizer was more prominent than iron. Foliar application of nTiO<sub>2</sub> positively affected some morphophysiological characteristics like as days to<em> </em>anthesis, chlorophyll content and straw yield. The results suggest that the delivery of Zn into barley seedling through spray of nano-fertilizer can be an efficient nutrient management strategy in semi-arid regions. Overall, our result indicated that the integration of nanotechnology in fertilizer products can improve fertilizer use efficiency and significantly increase of barley yield. However, plant response to nanoparticles significantly depend on concentration and time of application as well as size, shape, and surface functionalization of the particles.

scholarly journals Impact of titanium dioxide nanoparticles on purification and contamination of nematic liquid crystals

2017 ◽  
Vol 8 ◽  
pp. 2766-2770 ◽  
Author(s):  
Dmitrii Pavlovich Shcherbinin ◽  
Elena A Konshina
Keyword(s):  
Titanium Dioxide ◽  
Liquid Crystals ◽  
Titanium Dioxide Nanoparticles ◽  
Nematic Liquid Crystals ◽  
Ion Density ◽  
Ionic Contamination ◽  
The Impact

We have investigated the impact of titanium dioxide nanoparticles on the ionic contamination of liquid crystals. Nematic liquid crystals with high and low initial ionic contamination have been examined. It has been shown that titanium dioxide nanoparticles reduced the ion density of liquid crystals with high initial ionic contamination from 134.5 × 1012 cm−3 to 63.2 × 1012 cm−3. In the case of liquid crystals with low initial ionic contamination, the nanoparticles led to an insignificant increase of ion density from 19.8 × 1012 cm−3 to 25.7 × 1012 cm−3.

Changes in biological parameters of freshwater animals under the impact of various crystal modifications of titanium dioxide nanoparticles

2015 ◽  
Vol 8 (3) ◽  
pp. 309-318 ◽  
Author(s):  
I. I. Tomilina ◽  
V. A. Gremyachikh ◽  
L. P. Grebenyuk ◽  
E. A. Smirnov ◽  
E. I. Golovkina
Keyword(s):  
Titanium Dioxide ◽  
Titanium Dioxide Nanoparticles ◽  
Biological Parameters ◽  
The Impact ◽  
Crystal Modifications

scholarly journals Photoactive titanium dioxide nanoparticles modify heterotrophic microbial functioning

2021 ◽  
Author(s):  
Mirco Bundschuh ◽  
Jochen P. Zubrod ◽  
Marco Konschak ◽  
Patrick Baudy ◽  
Bianca Frombold ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Microbial Community ◽  
Leaf Litter ◽  
Titanium Dioxide Nanoparticles ◽  
Underlying Mechanism ◽  
Ecosystem Functions ◽  
Oxygen Species ◽  
Model Ecosystems ◽  
The Many ◽  
The Impact

AbstractNanoparticulate titanium dioxide (nTiO2) is frequently applied, raising concerns about potential side effects on the environment. While various studies have assessed structural effects in aquatic model ecosystems, its impact on ecosystem functions provided by microbial communities (biofilms) is not well understood. This is all the more the case when considering additional stressors, such as UV irradiation — a factor known to amplify nTiO2-induced toxicity. Using pairwise comparisons, we assessed the impact of UV (UV-A = 1.6 W/m2; UV-B = 0.7 W/m2) at 0, 20 or 2000 μg nTiO2/L on two ecosystem functions provided by leaf-associated biofilms: while leaf litter conditioning, important for detritivorous invertebrate nutrition, seems unaffected, microbial leaf decomposition was stimulated (up to 25%) by UV, with effect sizes being higher in the presence of nTiO2. Although stoichiometric and microbial analyses did not allow for uncovering the underlying mechanism, it seems plausible that the combination of a shift in biofilm community composition and activity together with photodegradation as well as the formation of reactive oxygen species triggered changes in leaf litter decomposition. The present study implies that the multiple functions a microbial community performs are not equally sensitive. Consequently, relying on one of the many functions realized by the same microbial community may be misleading for environmental management.

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