Effect Of Nano-titanium Dioxide Research Articles

Investigation of synergistic effect of nano sized Ag/TiO2 particles on antibacterial, physical and mechanical properties of UV-curable clear coatings by experimental design

Abstract The synergistic effect of nano titanium dioxide (10 and 30 nm) and nano silver (10 nm) as antibacterial agents were investigated on UV curable clear coating. Antibacterial and physical–mechanical properties of coating were optimized using experimental design in response surface method. Twenty different samples of nano Ag and nano TiO 2 were prepared in this method. Antibacterial properties on Gram-negative bacteria ( Escherichia coli ) were investigated. The results revealed that using equal amounts of two sizes of nano TiO 2 promote the antibacterial activity of nano Ag. So, the coating shows strong activity against E. coli . Physical–mechanical properties such as surface hardness, abrasion resistance, scratch resistance and gloss of the coating were evaluated. The results depicted appropriate physical–mechanical properties. Also, scanning electron microscope (SEM), atomic force microscope (AFM) and Fourier transform infrared (FT-IR) spectroscopy were used to study the effect of nano particles on coating properties.

The Nanostructure and Properties of the Nano TiO<sub>2</sub>/PVA Composite Film

In order to improve the performance of polyvinyl alcohol (PVA), the nanometer TiO2/PVA composite film prepared by solution casting, effects of nanotitanium dioxide (TiO2) PVA film. The structures, mechanical properties, and optical properties of the composite films were detected by infrared spectroscopy, TG, DSC, XRD. The results show that: nanoTiO2 fill added to the PVA matrix to improve the mechanical properties of PVA, thermal stability and UV shielding performance.

The Effect of Nano Titanium Dioxide on the Physicomechanical Properties and Heat Ageing of Low-Density Polyethylene

An examination was made of the effect of titanium dioxide (nano-TiO2, “Showa Denko”) on the physicomechanical properties of low-density polyethylene (LDPE). It was established that LDPE specimens filled with industrial titanium dioxide TiO2 of micron size and with nano-TiO2 “Showa Denko” exhibit different physicomechanical properties after composite preparation and thermooxidative ageing. In spite of a certain reduction in strength and elasticity after milling and pressing, the composite material containing nanopigment exhibits higher heat ageing resistance than material containing standard industrial titanium dioxide.

Improvement in thermo mechanical and optical properties of in situ synthesized PMMA/TiO2 nanocomposite

In this paper, transparent thin films of nano titania filled Poly(methyl methacrylate) (PMMA) composites were synthesized by solvent casting method using tetra hydro furan as a solvent, with in situ nonaqueous ‘sol-gel’ transformation involving the mixing of titanium isopropoxide (as sol-gel precursor) and methanol. The present research work is focused at studying the effect of titania loading on optical and mechanical behavior of transparent nano hybrid thin films. The effect of nano Titanium dioxide (TiO2) loading on PMMA morphology was studied by using a scanning electron microscope (SEM). Bowl shaped structures were obtained in pure PMMA thin film, which were deformed on incorporation of TiO2 nanoparticles. This nanocomposite exhibits enhanced optical and mechanical properties. The peak of UV absorption is blue shifted to 261 and 266 nm with the incorporation of TiO2. At this wavelength, the absorption is increased up to approximately 397%. The nanocomposites exhibit increased tensile strength up to 40% and modulus up to 16%. Tg of PMMA increased from 84.8 to 86.7 °C on adding 1.25% TiO2 nanoparticles.

A nitric oxide biosensor based on the photovoltaic effect of nano titanium dioxide on hemoglobin

A nitric oxide biosensor based on the photovoltaic effect of nano titanium dioxide on hemoglobin was fabricated with high sensitivity, selectivity, as well as stability. The linear detection concentration range was 5.0 × 10−6–4.0 × 10−4 M. The detection limit was 1.0 × 10−6 M with a sensitivity of 8 nA/μM. The possible coexisting compounds would not interfere with the nitric oxide detection.

Electrochemical investigation on the catalytic ability of tyrosinase with the effect of nano titanium dioxide

Tyrosinase, which is also named poly-phenol oxidase, has the ability to oxidize several kinds of phenolic compounds to homologous o-quinones. In this work, nano titanium dioxide particles (TiO 2 NPs) and tyrosinase are co-immobilized onto the surface of glassy carbon electrode to electrochemically study the effect of TiO 2 NPs on the catalytic activity of tyrosinase. And, the influence of the photovoltaic effect of this nanomaterial on the catalytic ability of this enzyme is especially investigated. It is found that TiO 2 NPs can greatly enhance the catalytic ability of tyrosinase. Moreover, the photovoltaic effect of this nanomaterial can further make tyrosinase to exhibit a higher enzymatic activity. This phenomenon may be due to the increasing amount of oxytyrosinase generated by the photovoltaic effect under ultraviolet (UV) light irradiation, which is an important intermediate in the process of the catalytic reactions.

Electrochemical study of photovoltaic effect of nano titanium dioxide on hemoglobin

Nano titanium dioxide (TiO 2) and hemoglobin (Hb) were co-modified on pyrolytic graphite (PG) electrode to study the photovoltaic effect of TiO 2 nanoparticles (NPs) on the electron transfer reactivity and catalytic activity of the protein. By means of cyclic voltammetry (CV) and FTIR measurements, the study was characterized in both aerobic and anaerobic environments. Experimental results revealed that the factors which mainly interacted with Hb were electron/hole pairs and reactive oxygen species (ROS) generated by the photovoltaic effect when TiO 2 NPs were irradiated under ultraviolet (UV) light. The electron/hole pairs generated on the surface of TiO 2 would influence the structure of Hb gently, so the electron transfer reactivity and catalytic ability of the protein slightly changed. In contrast, ROS interacted with Hb intensively, which brought in much conformational change to Hb and its active centers, and even cause some damage. Consequently, the electron transfer reactivity and catalytic activity of Hb changed with a process of increasing initially and decreasing afterwards.

Hemoglobin-Based Hydrogen Peroxide Biosensor Tuned by the Photovoltaic Effect of Nano Titanium Dioxide

The photovoltaic effect of titanium dioxide (TiO2) nanoparticles, induced by ultraviolet light, can greatly improve the catalytic activity of hemoglobin as a peroxidase, with the sensitivity increased nearly 3-fold and the detection limit lowered 2 orders, in contrast to the catalytic reactions in the dark, which indicates a possible method to tune the properties of proteins for development of photocontrolled protein-based biosensors.