1,721,017 research outputs found
Anti-inflammatory entrapment in Polycaprolactone/silica hybrid materials prepared by sol-gel route, characterization, bioactivity and vitro release behaviour
No full textAim: A novel organic/inorganic hybrid material, based on poly(ε-caprolactone) (PCL) and silica (SiO2), were synthesized by the sol-gel method. An anti-inflammatory agent (indomethacin) was incorporated into the hybrid material to verify its local controlled drug delivery system. Methods: The structure of the interpenetrating network was investigated by Fourier transform infrared spectroscopy. The morphology of the materials was studied by scanning electron microscopy. The structure of a molecular level dispersion was disclosed by atomic force microscopy. The bioactivity of the synthesized hybrid materials was revealed by the formation of a layer of hydroxyapatite on the surface of samples soaked in a simulated body fluid (SBF). Release kinetics in SBF were subsequently investigated. The amount of drug released was detected by UV-VIS spectroscopy. Results: Pure anti-inflammatory agent exhibited linear release with time; in contrast, sol-gel silica entrapped drugs were released with a logarithmic time dependence starting with an initial burst effect followed by a gradual decrease. Conclusions: SiO2/PCL (3, 6, 9 and 12%wt) materials, prepared via sol-gel process, are organic/inorganic hybrid and bioactive materials. All the materials showed a good release and therefore could be used as drug delivery syste
Release kinetics of anti-inflammatory drug, and characterization and bioactivity of SiO2+PCL hybrid material synthesized by sol-gel processing.
No full textBACKGROUND: Controlled and local drug delivery systems of anti-inflammatory agents are drawing increasing attention thanks to their possible pharmaceutical and biomedical applications. These systems have extended therapeutic effects and reduced side effects.
METHODS: A single-step sol-gel process was used to prepare organic-inorganic hybrid materials based on silica (SiO2) and poly-ε-caprolactone, containing ketoprofen for controlled drug delivery applications. Fourier transform infrared spectroscopy analysis proved formation of H-bonds among the carbonyl groups of the polymer chains and Si-OH group of the inorganic matrix. X-ray diffraction analysis highlighted the amorphous nature of the synthesized materials. Scanning electron microscopy and atomic force microscope topography showed their homogeneous morphology and nanostructure nature.
RESULTS: The bioactivity of the synthesized hybrid materials was shown by the formation of a layer of hydroxyapatite on the surface of samples soaked in a simulated body fluid (SBF).
CONCLUSION: Release kinetics in SBF were subsequently investigated by means of UV-VIS spectroscopy. A large amount of drug release occurred during the first few hours, then a slower drug release supplied a maintenance dose until the end of the experiment
Sol-gel hybrid materials for aerospace applications: Chemical characterization and comparative investigation of the magnetic properties
No full textSynthesis of SiO2 system via sol-gel process: Biocompatibility tests with a fibroblast strain and release kinetics
No full textSiO2 glass has been synthesized via sol-gel process and enriched with 5 wt % sodium ampicillin. To verify the biocompatibility of the obtained biomaterial, fibroblasts have been grown on a glass surface and were tested for viability after 24 h. The results of the Water-Soluble Tetrazolium (WST)-8 analysis suggest that SiO2 glass has an adequate biocompatibility. The amorphous nature of the gels has been ascertained by X-ray diffraction analysis. Release kinetics have been subsequently investigated in a simulated body fluid. The amount of sodium ampicillin released has been detected by ultraviolet-visible spectroscopy. The release kinetics seems to occur in more than one stage. High-performance liquid chromatography analysis has also been carried out to ensure the integrity of ampicillin after the synthesis treatment
Response of SAOS-2 cells to simulated microgravity and effect of biocompatible sol-gel hybrid coatings
No full textThe health of astronauts, during space flight, is threatened by bone loss induced by microgravity, mainly attributed to an imbalance in the bone remodeling process. In the present work, the response to the microgravity of bone cells has been studied using the SAOS-2 cell line grown under the condition of weightlessness, simulated by means of a Random Positioning Machine (RPM). Cell viability after 72 h of rotation has been evaluated by means of WST-8 assay and compared to that of control cells. Although no significant difference between the two cell groups has been observed in terms of viability, F-actin staining showed that microgravity environment induces cell apoptosis and altered F-actin organization. To investigate the possibility of hindering the trend of the cells towards the death, after 72 h of rotation the cells have been seeded onto biocompatible ZrO2/PCL hybrid coatings, previously obtained using a sol-gel dip coating procedure. WST-8 assay, carried out after 24 h, showed that the materials are able to inhibit the pro-apoptotic effect of microgravity on cells
Coatings of titanium substrates with xCaO·(1 - x)SiO<inf>2</inf> sol-gel materials: characterization, bioactivity and biocompatibility evaluation
No full textSurface modifications of titanium implants by coating with bioactive and biocompatible poly (ε-caprolactone)/SiO2 hybrids synthesized via sol-gel
No full textClass I organic/inorganic hybrid materials have been synthesized by sol-gel method from a multicomponent solution containing tetraethyl orthosilicate (TEOS), water, ethanol and nitric acid by adding different percentages of poly (ε-caprolactone) (PCL) dissolved in chloroform. Those hybrids have been used, in sol phase, to dip coat commercially pure titanium (CP Ti) grade 4 substrates with the aim of transferring to them the known biological properties of silica-based sol-gel materials. Particular attention has been directed to investigate the effect of PCL amount on both structure and coating performances.The chemical composition of the films was ascertained by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis. Scanning electron microscope (SEM) proved that polymer allows to make crack-free coatings.The biological performances of the un-coated and coated substrates were compared and evaluated by means of bioactivity test and WST-8 assay. SEM and energy dispersive X-ray (EDX) analyses have detected higher hydroxyapatite nucleation on the surface of the coated substrates after soaking in a fluid simulating the composition of the human blood plasma (SBF). Moreover, higher vitality of NIH 3T3 mouse embryonic fibroblast cells seeded on coated specimens was recorded. The results, thus, prove that coating application effectively improves the bioactivity and biocompatibility of CP Ti grade 4 substrates
Biocompatibility improvement of titanium implants by coating with hybrid materials synthesized by sol-gel technique
No full textOrganic-inorganic hybrid materials based on zirconia and polyethylene glycol (PEG) have been synthesized via sol-gel method in the present study. Those materials, still in the sol phase, have been used to coat a titanium grade 4 (Ti- 4) substrate to improve its biological properties. Dip-coating technique has been used to obtain thin films. PEG, a biocompatible polymer, used as the organic phase, has been incorporated with different percentages in an inorganic zirconiumbased matrix. Those hybrids have been characterized by Fourier transform infrared spectroscopy (FTIR) to detect interactions between the two phases. The films have been examined using SEM to detect morphological changes with PEG percentages. The potential applications of the hybrid coatings in biomedical field have been evaluated by bioactivity and cytotoxicity tests. The coated titanium was immersed in simulated body fluid (SBF) for 21 days and the hydroxyapatite deposition on its surface was subsequently evaluated, as that feature can be used as an index of bone-bonding capability. SEM equipped with energy dispersive spectrometer (EDS) was used to examine hydroxyapatite formation. NIH 3T3 mouse embryonic fibroblast cells were seeded on specimens to evaluate cells-materials interactions and cell vitality was inspected using WST-8 Assa
Surface Modifications for Implants Lifetime extension: An Overview of Sol-Gel Coatings
Full text linkThe limited lifetime of implants entails having patients undergo replacement surgeries, several times throughout life in young patients, with significant risks for them and extensive cost for healthcare service. The overcoming of such inconvenience is still today a hard challenge for the scholars of the biomedical and biomaterial fields. The improvement of the currently employed implants through surface modification by coatings application is the main strategy proposed to avoid implants failure, and the sol-gel coating is an ideal technology to achieve this goal. Therefore, the present review aims to provide an overview of the most important problems leading to implant failure, the sol-gel coating technology, and its use as a strategy to overcome such issues
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