1,720,989 research outputs found
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
Synthesis 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
PEG-based organic–inorganic hybrid coatings prepared by the sol–gel dip-coating process for biomedical applications
No full textIn the present work, the application of functional coatings on metallic implants was proposed to delay implant failure by improving tissue tolerance and implant osseointegration. Three bioactive and biocompatible organic–inorganic hybrid nanocomposites, consisting of polyethylene glycol (PEG) embedded in a SiO2, ZrO2, and TiO2 matrix, respectively, were synthesized via the sol–gel method. Materials in the sol phase were used to dip-coat titanium grade 4 substrates for use as dental and orthopedic implant models. To investigate the influence of the glass matrix and the polymer amount on the coating structure, and thus on their biological properties, several hybrids were obtained by adding different weight percentages of PEG to each glass matrix. Attenuated total reflectance Fourier transform infrared spectroscopy confirmed the presence of the polymer in the nanocomposites and scanning electron microscopy showed that an increase in the PEG content allows crack-free coatings to be obtained. Moreover, the bioactivity and biocompatibility of both the uncoated and coated titanium implants were investigated and compared by an in vitro test. The results revealed that coated substrates have more enhanced biological performance than the uncoated ones. The bioactivity is not significantly affected by either the inorganic matrix or the PEG amount, whereas the presence of polymer makes the films more biocompatible. POLYM. ENG. SCI., 57:478–484, 2017. © 2017 Society of Plastics Engineers
Influence of the polymer amount on bioactivity and biocompatibility of SiO2/PEG hybrid materials synthesized by sol-gel technique
No full textSiO2/PEG organic-inorganic hybrid materials, which differ in polyethylene glycol (PEG) content, were synthesized by sol-gel technique and the characterization of their structure and biological properties was carried out in order to evaluate the possible use in biomedical field. FT-IR spectroscopy detected that the two components of the hybrids (SiO2 and PEG) are linked by hydrogen bonds between the Si-OH groups of the inorganic phase and the terminal alcoholic groups and/or the ethereal oxygen atoms in the repeating units of polymer. X-ray diffraction analysis ascertained the amorphous nature of the gels and the observation of their morphology by SEM microscopy confirmed that the interpenetration of the two phases (organic and inorganic) occurs on nanometric scale. The biological characterization was carried out as a function of the polymer amount to study its influence on material behavior. The results showed that the synthesized materials were bioactive and biocompatible. The formation of a hydroxyapatite layer, indeed, was observed on their surface by SEM/EDX analysis after soaking in simulated body fluid. Moreover, the biocompatibility of SiO2/PEG hybrids was assessed performing MTT and SRB cytotoxicity tests on fibroblast cell NIH 3T3 after 24 and 48h of exposure, as well as Trypan Blue dye exclusion test. The response to the presence of the investigated materials was positive. The cell growth and proliferation showed dependence on polymer amount and time of exposure to the material extracts. Therefore, the obtained results are encouraging for the use of the obtained hybrids in dental or orthopedic applications.SiO2/PEG organic-inorganic hybrid materials, which differ in polyethylene glycol (PEG) content, were synthesized by sol-gel technique and the characterization of their structure and biological properties was carried out in order to evaluate the possible use in biomedical field. FT-IR spectroscopy detected that the two components of the hybrids (SiO2 and PEG) are linked by hydrogen bonds between the Si-OH groups of the inorganic phase and the terminal alcoholic groups and/or the ethereal oxygen atoms in the repeating units of polymer. X-ray diffraction analysis ascertained the amorphous nature of the gels and the observation of their morphology by SEM microscopy confirmed that the interpenetration of the two phases (organic and inorganic) occurs on nanometric scale. The biological characterization was carried out as a function of the polymer amount to study its influence on material behavior. The results showed that the synthesized materials were bioactive and biocompatible. The formation of a hydroxyapatite layer, indeed, was observed on their surface by SEM/EDX analysis after soaking in simulated body fluid. Moreover, the biocompatibility of SiO2/PEG hybrids was assessed performing MTT and SRB cytotoxicity tests on fibroblast cell NIH 3T3 after 24 and 48 h of exposure, as well as Trypan Blue dye exclusion test. The response to the presence of the investigated materials was positive. The cell growth and proliferation showed dependence on polymer amount and time of exposure to the material extracts. Therefore, the obtained results are encouraging for the use of the obtained hybrids in dental or orthopedic applications
Preparation of 0.7SiO<inf>2</inf>·0.3CaO/PCL hybrid layers via sol–gel dip coating for the surface modification of titanium implants: characterization, bioactivity and biocompatibility evaluation
No full textCorrosion behavior and mechanical properties of bioactive sol-gel coatings on titanium implants
No full textOrganic-inorganic hybrid coatings based on zirconia and poly (ε-caprolactone) (PCL) were prepared by means of sol-gel dip-coating technique and used to coat titanium grade 4 implants (Ti-4) in order to improve their wear and corrosion resistance. The coating chemical composition has been analysed by ATR-FTIR. The influence of the PCL amount has been investigated on the microstructure, mechanical properties of the coatings and their ability to inhibit the corrosion of titanium. SEM analysis has shown that all coatings have a nanostructured nature and that the films with high PCL content are crack-free. Mechanical properties of the coatings have been studied using scratch and nano-indentation tests. The results have shown that the Young's modulus of the coatings decreases in presence of large amounts of the organic phase, and that PCL content affects also the adhesion of the coatings to the underlying Ti-4 substrate. However, the presence of cracks on the PCL-free coatings affects severely the mechanical response of the samples at high loads. The electrochemical behavior and corrosion resistance of the coated and uncoated substrate has been investigated by polarization tests. The results have shown that both the coatings with or without PCL don't affect significantly the already excellent passivation properties of titaniu
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