29 research outputs found

    Comparison study on the properties of the CaP coatings formed by RF-magnetron sputtering of the Mg- and Sr-substituted ß-tricalcium phosphate and hydroxyapatite

    Get PDF
    This article describes the influence of Mg and Sr substitutions in the structure of -tricalcium phosphate and hydroxyapatite powder targets on the deposition rate of coatings formed via RF-magnetron sputtering and their properties. It was revealed that even low doses of ionic substitutions in -tricalcium phosphate significantly affect deposition rate, morphology and physico-chemical properties of respective coatings. Similar doses of these substitutions in hydroxyapatite are not enough to influence the deposition rate, but they affect coating properties

    Influence of magnesium and strontium substitutions in the structure of hydroxyapatite lattice on the deposition rate and properties of the CaP coatings formed via RF-sputtering of the powder targets

    Get PDF
    This work is dedicated to studying of the properties of the calcium phosphate (CaP) coatings deposited on Ti substrates by radio-frequency magnetron sputtering (RFMS) of three hydroxyapatite-based powder targets: pure hydroxyapatite (HA), Mg-substituted HA (Mg-HA, Mg = 0.93 ± 0.13 at.%) and Sr-substituted HA (Sr-HA, Sr ∼ 0.47 at.%). The influence of ionic substitutions in the structure of the sputtered targets on the surface morphology, physicochemical properties of the coatings and their wettability were studied. It is revealed that Mg and Sr ionic substitutions in the crystal lattice of HA at these concentrations don't affect deposition rate, however, it influences morphology, wettability and elemental and phase composition of deposited coatings

    Composite biphase coatings formed by hybrid technology for biomedical applications

    Get PDF
    Calcium-phosphate (CaP) coatings were formed via combining methods of microarc oxidation (MAO) and radiofrequency magnetron sputtering (RFMS). SEM, XPS, XRD and nanoindentation methods were used to study physico-chemical and mechanical properties of the coatings. It was revealed that the upper CaP layer changes the morphology of the coatings at the microscale and increases the Ca/P ratio of biphasic coatings

    Controlled drug release from electrospun PCL non-woven scaffolds via multi-layering and e-beam treatment

    Get PDF
    Currently, electrospun synthetic bioresorbable polymer scaffolds are applied in regenerative medicine and tissue engineering as targeted drug delivery devices because of their mechanical and physico-chemical properties. To control the rate of polymer degradation and drug release from polymer scaffolds, surface modification techniques are widely used. In this study, paracetamol-loaded poly (ε-caprolactone) electrospun fibrous scaffolds were treated by the pulsed electron beam irradiation. Pure control PCL scaffold, as well as scaffolds with four paracetamol concentrations (2 wt./wt. %, 8 wt./wt. %, 16 wt./wt. %, and 32 wt./wt.%) were modified. The mechanical and chemical properties and morphology of modified materials were examined. The sustained release of the model drug over a period of one hour for both non-treated and treated samples was demonstrated. It was shown that treatment leads to an increase in drug release rate and does not change surface morphology of scaffolds and fibers diameter distribution

    Reactive magnetron plasma modification of electrospun PLLA scaffolds with incorporated chloramphenicol for controlled drug release

    Get PDF
    Surface modification with the plasma of the direct current reactive magnetron sputtering has demonstrated its efficacy as a tool for enhancing the biocompatibility of polymeric electrospun scaffolds. Improvement of the surface wettability of materials with water, as well as the formation of active chemical bonds in the near-surface layers, are the main reasons for the described effect. These surface effects are also known to increase the release rate of drugs incorporated in fibers. Herein, we investigated the effect of plasma modification on the chloramphenicol release from electrospun poly (lactic acid) fibrous scaffolds. Scaffolds with high—50 wt./wt.%—drug content were obtained. It was shown that plasma modification leads to an increase in the drug release rate and drug diffusion coefficient, while not deteriorating surface morphology and mechanical properties of scaffolds. The materials’ antibacterial activity was observed to increase in the first day of the experiment, while remaining on the same level as the unmodified group during the next six days. The proposed technique for modifying the surface of scaffolds will be useful for obtaining drug delivery systems with controlled accelerated release, which can expand the possibilities of local applications of antibiotics and other drugs

    Experimental Evaluation of Russian Anode Layer Thrusters

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76973/1/AIAA-1994-3010-800.pd

    Effect of pulsed electron beam treatment on the release profile of chloramphenicol from polylactic acid–based polymeric scaffolds

    No full text
    The paper presents the results of testing the properties of antibacterial nonwoven fibrous materials based on polylactic acid with incorporated chloramphenicol. It has been shown that exposure to a pulsed electron beam increased the rate of release of chloramphenicol into a phosphate-buffered saline medium. In this case, the amount of the substance released from treated samples was reliably greater than that with untreated samples during the five days of the experiment

    Properties of calcium-phosphate coatings formed by pulsed laser deposition

    No full text
    The paper is dedicated to the research of calcium-phosphate coatings formed on the surface of the polymer layers (copolymer tetrafluoroethylene with vinylidene fluoride) by pulsed laser deposition. The calcium-phosphate coatings were formed using two different by composition targets. The morphology of the obtained coatings was analyzed by Scanning Electron Microscopy, the elemental composition was analyzed by Energy Dispersive Analysis, and the chemical composition was analyzed by Fourier Transform Infrared Spectroscopy
    corecore