Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
enabled [disable] Abstract
Number of results

Results found: 4

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  functionalization
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
EN
Hybrid nanofillers of silica grafted with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane were obtained by the method based on solvent evaporation with the use of both hydrated or emulsion spherical silica. Octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane was applied as a modifying agent and it was synthesized by employing the hydrosilylation reaction. The effectiveness of modification of the hybrid nanofillers obtained was verified using Fourier transform infrared spectroscopy and nuclear magnetic resonance (29Si and 13C CP MAS NMR). The products obtained were characterized by determination of their physicochemical properties and porous structure, including specific surface area, pore diameter and pore volume. Dispersion degree and particle size of the nanofillers was characterized by NIBS (Non-Invasive Back-scatter) method and laser diffraction technique, while their morphology by transmission electron microscopy.
EN
Polyethylene terephthalate (PET) foils have been exposed to oxygen plasma and its afterglow in order to reveal compositional and structural modifications of the surface layer. Oxygen plasma was created by electrode-less RF discharge in a glass chamber so the O-atom density was close to 1022 m-3 although the density of charged particles was only about 1 × 1016 m-3. Long-living reactive particles created in plasma were leaked into the afterglow chamber using a two-stage rotary pump of pumping speed 4.4 × 10-3 m3 s-1. The density of O-atoms in the afterglow as measured with a catalytic probe was 3 × 1021 m-3, while the density of reactive oxygen molecules was estimated theoretically. The functionalization was accomplished even after a brief exposure to either plasma or afterglow since all samples were saturated with oxygen-rich functional groups as revealed by XPS. The water contact angle measurements, however, showed that only plasma treatment allowed for super-hydrophilicity, explained by rich surface morphology as detected by AFM. The differences in morphological properties between plasma and afterglow treated samples were explained by different interaction mechanisms between low and high energy particles impinging the polymer surface.
EN
Chloroperoxidase from Caldariomyces fumago was immobilized in Eupergit® C, a commercial mesoporous acrylic-based material. Due to low stability of the enzyme under neutral and basic pH, the usual covalent immobilization procedures cannot be applied to this enzyme. Several strategies were followed in order to achieve a stable interaction between the protein and the support. The support was efficiently functionalized with different reactive groups such as aromatic and aliphatic amines, glutaraldehyde, diazonium ions, and maleimide moieties; solvent-exposed amino acid residues in chloroperoxidase were identified or created through chemical modification, so that they were reactive under conditions where the enzyme is stable. Enzyme load and retained activity were monitored, obtaining biocatalysts with specific activity ranging from 200 to 25,000 U/g. The highest load and activity was obtained from the immobilization of a chemically-modified CPO preparation bearing a solvent-exposed free thiol group. This biocatalyst efficiently catalyzed the transformation of β-estradiol, an endocrine disruptor.
4
63%
EN
Porous anodic alumina (PAA) is a biomaterial based on a cost-effective electrochemical anodization of pure aluminum with unique geometrical properties, i.e., self-ordering hexagonal pore distribution, tunable pore diameters and interpore distances, and uniformity of the pores in the vertical direction (nanochannels). These remarkable properties have found important applications in several fields such as energy storage, optics, photonics, magnetism, catalysis and, in particular, in the biomedicine field. In this work, we review the current state of research and key issues on cell culture and implants, drug delivery systems with complex release profiles and specific action, and high efficiency and sensitivity biosensors with different biosensing mechanisms, all of them based on PAA. The biocompatibility, morphology of the surface, nanoestructural engineering in-depth, surface functionalization and coatings are discussed and analyzed in detail.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.