scholarly journals Polypropylene Graft Poly(methyl methacrylate) Graft Poly(N-vinylimidazole) as a Smart Material for pH-Controlled Drug Delivery

2021 ◽  
Vol 23 (1) ◽  
pp. 304
Author(s):  
Felipe López-Saucedo ◽  
Jesús Eduardo López-Barriguete ◽  
Guadalupe Gabriel Flores-Rojas ◽  
Sharemy Gómez-Dorantes ◽  
Emilio Bucio
Keyword(s):  
Methyl Methacrylate ◽  
Gamma Rays ◽  
Photoelectron Spectroscopy ◽  
Controlled Drug Delivery ◽  
Controlled Drug Release ◽  
Physicochemical Analysis ◽  
Glycopeptide Antibiotics ◽  
X Ray ◽  
Simultaneous Irradiation ◽  
New Material

Surface modification of polypropylene (PP) films was achieved using gamma-irradiation-induced grafting to provide an adequate surface capable of carrying glycopeptide antibiotics. The copolymer was obtained following a versatile two-step route; pristine PP was exposed to gamma rays and grafted with methyl methacrylate (MMA), and afterward, the film was grafted with N-vinylimidazole (NVI) by simultaneous irradiation. Characterization included Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and physicochemical analysis of swelling and contact angle. The new material (PP-g-MMA)-g-NVI was loaded with vancomycin to quantify the release by UV-vis spectrophotometry at different pH. The surface of (PP-g-MMA)-g-NVI exhibited pH-responsiveness and moderate hydrophilicity, which are suitable properties for controlled drug release.

scholarly journals Polypropylene Graft Poly(Methyl Methacrylate) Graft Poly(N-Vinylimidazole) as a Smart Material for pH-Controlled Drug Delivery

2021 ◽  
Author(s):  
Felipe López-Saucedo ◽  
Jesús Eduardo López-Barriguete ◽  
Guadalupe Gabriel Flores-Rojas ◽  
Sharemy Gómez-Dorantes ◽  
Emilio Bucio
Keyword(s):  
Antimicrobial Activity ◽  
Methyl Methacrylate ◽  
Gamma Rays ◽  
Photoelectron Spectroscopy ◽  
Controlled Drug Delivery ◽  
Controlled Drug Release ◽  
Physicochemical Analysis ◽  
X Ray ◽  
Simultaneous Irradiation ◽  
Scanning Electron

Surface modification of polypropylene (PP) films is achieved using gamma-irradiation-induced grafting to proffer with antimicrobial activity. The copolymer was obtained through a versatile two-step route; pristine PP is exposed to gamma rays and grafted using methyl methacrylate (MMA), then N-vinylimidazole (NVI) is grafted onto the copolymer PP-g-MMA by simultaneous irradiation. The characterization included Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Thermogravimetric Analysis (TGA), X-ray Photoelectron Spectroscopy (XPS), and physicochemical analysis of swelling and contact angle. The copolymer (PP-g-MMA)-g-NVI was loaded with vancomycin, and the drug released was quantified by UV-vis spectrophotometry at different pH. The surface of (PP-g-MMA)-g-NVI exhibited pH-responsiveness and moderate hydrophilicity, suitable properties for controlled drug release.

Two-Phase Structure of Fluorinated Powdered Silica Resulting from Deep Processing of Rice Wastes

2018 ◽  
Vol 7 (1) ◽  
pp. 38-44 ◽  
Author(s):  
А. Рашковский ◽  
A. Rashkovskiy ◽  
Е. Политова ◽  
E. Politova ◽  
А. Меркушкин ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Inductively Coupled Plasma ◽  
Physicochemical Analysis ◽  
Nano Particles ◽  
Deep Processing ◽  
X Ray Diffraction ◽  
Two Phase ◽  
X Ray ◽  
Inductively Coupled ◽  
Two Phases

In this investigation the structure of «green» silica maid with rice husk has been studied by methods of physicochemical analysis. By method of X-ray diffraction it has been found that the samples of «green» silica powders are completely amorphous, and the observed amorphous halo consists of two components. By method of scanning electron microscopy it has been revealed that nano-particles of «green» SiO2 can form agglomerates and microstructures with dimensions from 0,1 to 500 microns, containing numerous pores, which presence has been confirmed by sorption measurements. By method of mass spectrometry with inductively coupled plasma has been found the presence of aluminum, titanium and nickel mechanical impurities in the «green» SiO2 powders. By method of X-ray photoelectron spectroscopy significant amount of fluorine atoms in «green» silica (up to 5% (at.)) has been revealed, which could be introduced in SiO2 in the process of its preparation. In such a case, it was found that fluorine interacts with «green» silica by means of two mechanisms, leading to appearance of two phases within fluorinated powders of «green» SiO2.

scholarly journals Synthesis of Selected Mixed Oxide Materials with Tailored Photocatalytic Activity in the Degradation of Tetracycline

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5361
Author(s):  
Katarzyna Siwińska-Ciesielczyk ◽  
Angelika Andrzejczak ◽  
Dominik Paukszta ◽  
Adam Piasecki ◽  
Dariusz Moszyński ◽  
...  
Keyword(s):  
Mixed Oxide ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Degradation Products ◽  
Sol Gel ◽  
Reaction System ◽  
Physicochemical Analysis ◽  
Oxide Materials ◽  
Oxidation Activity ◽  
X Ray

The elimination of antibiotics occurring in the natural environment has become a great challenge in recent years. Among other techniques, the photocatalytic degradation of this type of pollutant seems to be a promising approach. Thus, the search for new photoactive materials is currently of great importance. The present study concerns the sol–gel synthesis of mono, binary and ternary TiO2-based materials, which are used as active photocatalysts. The main goal was to evaluate how the addition of selected components—zirconium dioxide (ZrO2) and/or zinc oxide (ZnO)—during the synthesis of TiO2-based materials and the temperature of thermal treatment affect the materials’ physicochemical and photocatalytic properties. The fabricated mixed oxide materials underwent detailed physicochemical analysis, utilizing scanning-electron microscopy (SEM), X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), energy-dispersive X-ray spectroscopy (EDS), low-temperature N2 sorption (BET model), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The synthesized mixed oxide materials were used as photocatalysts in the heterogeneous photodegradation of tetracycline (TC). The physicochemical properties of the fabricated photocatalysts, including morphology, crystalline and textural structure, as well as the pH of the reaction system in the photocatalytic tests, were taken into account in determining their photo-oxidation activity. LC–MS/MS analysis was used to identify the possible degradation products of the selected antibiotic.

Oxidative removal of As(III) by polyacrylonitrile@Ag-Ag2O/schwertmannite nanofiber under visible light

2022 ◽  
pp. 152808372110569
Author(s):  
Jing Han ◽  
Hai-Tao Ren ◽  
Ting-Ting Li ◽  
Bing-Chiuan Shiu ◽  
Yong-Gui Li ◽  
...  
Keyword(s):  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Photogenerated Electron ◽  
Light Response ◽  
Precipitation Reaction ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Oxidative Removal ◽  
Electron Microscopy Analysis ◽  
New Material

Visible light response PAN@Ag-Ag2O/Sch (PAN@AS, schwertmannite and polyacrylonitrile abbreviated as Sch and PAN) nanofibers with different mass ratios were synthesized by electrospinning technology and pH-induced precipitation reaction. X-Ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy analysis showed that the formation of Ag-Ag2O/Sch heterojunction and Ag-Ag2O nanoparticles were evenly distributed on the surface of Sch. The prepared nanofibers have high oxidative removal performance for As(III) under visible light. In the [email protected] system, the total As removal percent can reach 90.96% after 120 min irradiation at pH 4.0. The scavenger experiments confirmed that the main active substances of the [email protected] system were h+ and •OH. The high oxidation and removal performance of the [email protected] composite for As(III) was attributed to the effective separation of photogenerated electron-hole pairs and high adsorption capacity of Sch for As under acidic conditions. This research provides a new material for the oxidation and removal of pollutants in water [such as As(III)] and also provides a research basis for the preparation of recyclable photocatalysts.

An ESCA and SEM Study of Changes in the Surface Composition and Morphology of Low-Calcium Coal Fly Ash as a Function of Aqueous Leaching

1986 ◽  
Vol 86 ◽  
Author(s):  
Myra M. Soroczak ◽  
H. C. Eaton ◽  
M. E. Tittlebaum
Keyword(s):  
Fly Ash ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Coal Fly Ash ◽  
Near Surface ◽  
X Ray ◽  
Sem Study ◽  
Before And After ◽  
New Material ◽  
Surface Chemistries

ABSTRACTThe reactivity of coal fly ash is dependent on the chemical composition of the surface. As reactions occur the ash particle size decreases and new material is available for reaction. This means that the near-surface chemistry can also be important. In the present study the surface chemistries of three ashes are determined by x-ray photoelectron spectroscopy both before and after exposure to a hydrating/leaching environment. Scanning electron microscopy is used to reveal ash morphology. The concentration of sulfur, found at the ash surfaces as a sulfate, and sodium decreased after leaching while the amount of iron and aluminum increased. Other elements, including calcium, increased and decreased with leaching depending on which ash was analyzed. Changes which occurred in the ash morphology after the removal of leachable elements are discussed.

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