thin films
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- MeSH
- cytotoxické testy imunologické metody MeSH
- hydroxyapatity aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- keramika aplikace a dávkování terapeutické užití účinky záření MeSH
- lasery MeSH
- lymfocyty cytologie MeSH
- techniky in vitro MeSH
- titan aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- zubní implantáty aplikace a dávkování MeSH
Titanium dioxide (TiO2) and Ag-incorporated diamond-like carbon (DLC) films were prepared on different substrates. The films were prepared by pulsed laser deposition (PLD). TiO2 and Ag were selected due to their potential values as biomaterials. Silver is effective against a wide range of spectrum including Gram-negative and Gram-positive bacteria and yeast. TiO2 and Ag-incorporated DLC thin films are suitable candidates for application on biomedical devices and implants due to their biocompatibility, chemical inertness, and mechanical properties. Thin films are widely used in coronary artery stents, dental implants, heart valves and other vascular devices. The microstructure and antibacterial properties of TiO2 and silver-doped diamond-like carbon (DLC) films have been investigated. The films structural quality was evaluated using SEM microscopy, AFM microscopy and Raman spectroscopy. The antibacterial activity was determined using Gram-negative bacteria Escherichia coli and Gram-positive bacteria Bacillus subtilis. Our results demonstrate that the TiO2, nitrogen doped titanium oxides TON and Ag-incorporated DLC films are potentially useful as biomedical materials having good antibacterial properties.
The increasing application of conductive polymers in electronics requires a precise and controlled deposition of these materials in thin layers. The article provides a brief description of the method, the principle and properties of both the source polymer and the matrix; also the experimental conditions necessary for successful thin layer pre¬paration are presented. Matrix-assisted pulsed laser eva¬poration of polypyrrole was carried out at different laser fluences (0.10.6 J cm2) with KrF excimer laser (λ = 248 nm) from water and dimethyl sulfoxide matrices and also with Nd:YAG laser (λ = 266 nm) for comparison. The layer thickness was hundreds of nanometers. The relations of the laser wavelength, laser fluence and the used matrix on the one hand and chemical composition of the layers (analyzed by FTIR) on the other were studied. The ablation threshold was 0.250.30 J cm2 for dimethyl sulfoxide matrix.
The diffusive gradient in the film technique (DGT) is a new approach to the in-situ determinations of labile metal species in aquatic systems. The DGT device accumulates labile species from solution and therefore contamination problems associated with conventional collection and filtration procedures are eliminated. The technique employs a hydrogel layer to control the diffusive transport of metals to a cation-exchange resin, which is selective for free or weakly complexed metal ion species. This study deals with the use of a new resin based on the Spheron-Oxin® ion exchanger in the DGT technique. The resin with a selectivity for trace metal species higher than Chelex 100 could provide more information on metal speciation in aquatic systems. Its performance was tested for Cd, Cu, Ni and Pb under laboratory conditions. The new resin provides reliable results in the pH range 6-8, independently of ionic strength (25 mmol l-1- 0.6 mol l-1) and also in the presence of Mg(NO3)2 (10 µmol l-1 - 0.05 mol l-1). The effect of iminodiacetic acid, as a model competitive ligand on the metal uptake measured by DGT probe was also assessed.
We report a new approach to characterization of thin (bio)molecular films based on spectroscopy of Bragg-scattered surface plasmons (BSSPs) generated by diffraction-coupling of counterpropagating surface plasmons on a metal-coated diffraction grating. The BSSPs exhibit fields with different penetration depths into the medium adjacent to the metal and therefore exhibit unequal sensitivities to the presence of (bio)molecular films on the surface of the metal. Therefore, spectroscopy of BSSPs enables in situ observation of the formation of biomolecular films and determination of both their refractive index and thickness. We demonstrate this capacity of spectroscopy of BSSPs in a model experiment in which growth of protein layers on a gold surface is studied.
Recently, diamondlike carbon (DLC) thin films have gained interest for biological applications, such as hip and dental prostheses or heart valves and coronary stents, thanks to their high strength and stability. However, the biocompatibility of the DLC is still questionable due to its low wettability and possible mechanical failure (delamination). In this work, DLC:N:O and DLC: SiOx thin films were comparatively investigated with respect to cell proliferation. Thin DLC films with an addition of N, O, and Si were prepared by plasma enhanced CVD from mixtures of methane, hydrogen, and hexamethyldisiloxane. The films were optically characterized by infrared spectroscopy and ellipsometry in UV-visible spectrum. The thickness and the optical properties were obtained from the ellipsometric measurements. Atomic composition of the films was determined by Rutherford backscattering spectroscopy combined with elastic recoil detection analysis and by x-ray photoelectron spectroscopy. The mechanical properties of the films were studied by depth sensing indentation technique. The number of cells that proliferate on the surface of the prepared DLC films and on control culture dishes were compared and correlated with the properties of as-deposited and aged films. The authors found that the level of cell proliferation on the coated dishes was high, comparable to the untreated (control) samples. The prepared DLC films were stable and no decrease of the biocompatibility was observed for the samples aged at ambient conditions.
- MeSH
- biokompatibilní materiály chemická syntéza chemie MeSH
- buněčné linie MeSH
- chemické jevy MeSH
- krevní plazma MeSH
- myoblasty fyziologie MeSH
- myši MeSH
- proliferace buněk * MeSH
- spektrální analýza MeSH
- testování materiálů * MeSH
- uhlík toxicita MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of this study is to consider the relevance of in situ measurements of bovine serum film thickness in the optical test device that could be related to the function of the artificial hip joint. It is mainly focussed on the effect of the hydrophobicity or hydrophilicity of the transparent surface and the effect of its geometry. Film thickness measurements were performed using ball-on-disc and lens-on-disc configurations of optical test device as a function of time. Chromatic interferograms were recorded with a high-speed complementary metal-oxide semiconductor digital camera and evaluated with thin film colorimetric interferometry. It was clarified that a chromium layer covering the glass disc has a hydrophobic behaviour which supports the adsorption of proteins contained in the bovine serum solution, thereby a thicker lubricating film is formed. On the contrary, the protein film formation was not observed when the disc was covered with a silica layer having a hydrophilic behaviour. In this case, a very thin lubricating film was formed only due to the hydrodynamic effect. Metal and ceramic balls have no substantial effect on lubricant film formation although their contact surfaces have relatively different wettability. It was confirmed that conformity of contacting surfaces and kinematic conditions has fundamental effect on bovine serum film formation. In the ball-on-disc configuration, the lubricant film is formed predominantly due to protein aggregations, which pass through the contact zone and increase the film thickness. In the more conformal ball-on-lens configuration, the lubricant film is formed predominantly due to hydrodynamic effect, thereby the film thickness is kept constant during measurement.
- MeSH
- adsorpce MeSH
- biomechanika MeSH
- hydrofobní a hydrofilní interakce MeSH
- interferometrie metody MeSH
- kyčelní protézy * MeSH
- lubrikanty chemie MeSH
- sérum chemie MeSH
- skot MeSH
- smáčivost MeSH
- testování materiálů metody MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
