Sol–gel preparation of titanium dioxide nanoparticles in presence of a linear polysaccharide

2009 ◽  
Vol 4 (4) ◽  
pp. 187-191 ◽  
Author(s):  
H.A. Monreal ◽  
A. Martínez-Villafañe ◽  
P.G. Casillas ◽  
C.A. Martínez ◽  
U. Arce-Colunga ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Gel Preparation

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.

Composition and Properties of TiO2 Sol to Produce a Photocatalytic Composite Material

2020 ◽  
Vol 854 ◽  
pp. 45-50
Author(s):  
Ekaterina N. Gubareva ◽  
Valeria V. Strokova ◽  
Yulia N. Ogurtsova ◽  
Pavel S. Baskakov ◽  
Lok Pratap Singh
Keyword(s):  
Composite Material ◽  
Titanium Dioxide ◽  
Ethyl Alcohol ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Component Composition ◽  
Optimal Composition ◽  
Optimal Ratio ◽  
Nanosized Titanium Dioxide ◽  
Sol Gel Synthesis

The paper presents the process of sol-gel synthesis of titanium dioxide nanoparticles, the peculiarities of the influence of component composition (titanium precursor content, solvent and stabilizer − surfactant) on the properties of sol and powder obtained on its basis. As a result of the study, the nature of the influence of the type and content of the surfactant in the solution of tetrabutoxytitanium in ethanol on the size of the synthesized particles of titanium dioxide was revealed. The optimal composition of the reaction mixture of TiO–R sol was obtained and the optimal ratio of tetrabutoxytitanium and ethyl alcohol was revealed using which a material with a high content of nanosized titanium dioxide was obtained.

Photoconversion of CO2 using copper-modified titanium dioxide nanoparticles

2011 ◽  
Vol 76 (11) ◽  
pp. 1335-1346 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao
Keyword(s):  
Titanium Dioxide ◽  
Photoelectron Spectroscopy ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Chemical Properties ◽  
High Photocatalytic Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Illumination ◽  
One Step

A series of copper-modified titanium dioxide (Cu/TiO2) nanoparticles were synthesized via one-step sol-gel method. The crystal structure and chemical properties were characterized using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Cu/TiO2nanoparticles were applied to CO2photoconversion and the yield of formaldehyde was used to evaluate the photocatalytic performance. The optimum amount of copper modifying was 0.6 wt.% and the yield of formaldehyde was 946 μmol/gcatunder UV illumination for 6 h. 20 wt.% Cu/TiO2also performed a high photocatalytic activity, which yielded 433 μmol/gcatformaldehyde under UV illumination for 6 h.

Sol–gel preparation and photocatalysis of titanium dioxide

2004 ◽  
Vol 96 (3) ◽  
pp. 119-126 ◽  
Author(s):  
C. Su ◽  
B.-Y. Hong ◽  
C.-M. Tseng
Keyword(s):  
Titanium Dioxide ◽  
Sol Gel ◽  
Gel Preparation

scholarly journals Photocatalytic Degradation of Organics by Using Nanocrystalline Titania

2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Sana Ahmad ◽  
Anam Nazir ◽  
Tousif Hussain
Keyword(s):  
Titanium Dioxide ◽  
Catalytic Activity ◽  
Titanium Dioxide Nanoparticles ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Crystalline Form ◽  
Titanium Butoxide ◽  
Fine Spray ◽  
Ft Ir

Titanium dioxide nanoparticles were prepared by a modified sol-gel route. Titanium butoxide was used as precursor and nebulizer was used for a fine spray of particles. The prepared powders were characterized by FT-IR, SEM, XRD, and TGA-DTA methods. The results indicated that nanoparticles with small size and high surface area were synthesized. XRD result indicated that TiO2 nanoparticles were obtained in pure anatase crystalline form with a crystallite size of 40 nm. The catalytic activity of as-synthesized nanoparticles was tested for the degradation of formic acid and toluene.

scholarly journals Synthesis and Characterization of Anatase Titanium Dioxide Nanoparticles Using Egg White Solution via Sol-Gel Method

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Samira Bagheri ◽  
Kamyar Shameli ◽  
Sharifah Bee Abd Hamid
Keyword(s):  
Titanium Dioxide ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Egg White ◽  
Gelling Agent ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Egg White Proteins

Anatase titanium dioxide nanoparticles (TNPs) are synthesized by a simple and cost-effective process with and without freshly water-soluble egg white proteins (albumin) via sol-gel method. The main advantage of using egg white proteins as a gelling agent is that it can provide long-term stability for nanoparticles by preventing particles agglomeration. The X-ray diffraction and FTIR results indicate that the synthesized nanoparticles have only the anatase structure without the presence of any other phase impurities. Additionally, the TNPs are characterized by a number of techniques such as thermogravimetric analysis (TGA), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet visible spectra (UV-vis). The sizes of titanium dioxide nanoparticles with and without using egg white solution are12.55±3.42 nm and21.45±4.21 nm, respectively. The results indicate that egg white solution is a reliable and cheap green gelling agent that can be used as a matrix in the sol-gel method to synthesis tiny size TNPs.

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