Sol–Gel Coating of Hydroxyapatite on Zirconia Substrate

The zirconia used in dental implants requires excellent mechanical and chemical properties such as high strength, high biological performance, corrosion resistance, and phase stability. In this study, after we prepared a highly fluidized solution of calcium phosphate, we fabricated a hydroxyapatite (HA) coating layer on a zirconia substrate using the sol–gel method to enhance its biocompatibility and bone-bonding ability. We dipped the zirconia substrate into the calcium phosphate sol to obtain the HA-coated film, which was dried at room temperature. The phase change and microstructural evolution were examined while the coating dried and during heat treatment. The biological activity of the coated and as-received substrates was evaluated using an in vitro experiment and the results were compared. The HA-coated film showed a highly dense and uniform layer structure, while its physical and biological properties depended on the starting substrate, coating times, and processing conditions.

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Developing a novel magnesium calcium phosphate/sodium alginate composite cement with high strength and proper self-setting time for bone repair

Journal of Biomaterials Applications ◽

10.1177/08853282211021535 ◽

2021 ◽

pp. 088532822110215

Author(s):

Haosheng He ◽

Haohao Ren ◽

Zhengwen Ding ◽

Mizhi Ji ◽

Hong Chen ◽

...

Keyword(s):

Calcium Phosphate ◽

Sodium Alginate ◽

Bone Repair ◽

Setting Time ◽

High Strength ◽

Biological Properties ◽

Mouse Bone Marrow ◽

Marrow Mesenchymal Stem Cells ◽

Composite Cements

In this work, novel magnesium calcium phosphate/sodium alginate composite cements were successfully fabricated with a proper setting time (5–24 min) and high compressive strength (91.1 MPa). The physicochemical and biological properties of the cement in vitro were fully characterized. The composite cements could gradually degrade in PBS as the soaking time increase, and the weight loss reached 20.74% by the end of 56th day. The cements could induce the deposition of Ca–P layer in SBF. Cell experiments proved that the extracts of the composite cements can effectively promote the proliferation and differentiation of the mouse bone marrow mesenchymal stem cells (MSCs). These preliminary results indicate that the magnesium calcium phosphate/sodium alginate composite cements could be promising as potential bone repair candidate materials.

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Synthesis, Characterization and In Vitro Evaluation of Strontium-Containing Sol-Gel Derived Bioactive Glass/ Biphasic Calcium Phosphate Nanocomposite

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.467.64 ◽

2013 ◽

Vol 467 ◽

pp. 64-69 ◽

Cited By ~ 1

Author(s):

Nader Nezafati ◽

Saeed Hesaraki ◽

Mohammad-Reza Badr-Mohammadi

Keyword(s):

Calcium Phosphate ◽

Bioactive Glass ◽

Biphasic Calcium Phosphate ◽

Bending Strength ◽

Sol Gel ◽

Physical And Mechanical Properties ◽

Sharp Decrease ◽

Biological Properties ◽

Different Temperatures

In the present research, strontium containing nanobioactive glass (NBG-Sr) was synthesized by sol-gel method. The morphology was analyzed by transmission electron microscope (TEM). Different amounts (0.5 to 5 wt%) of NBG-Sr were then added to biphasic calcium phosphate (BCP). They were sintered at different temperatures, i.e., 1100, 1200 and 1300 °C and changes in physical and mechanical properties were investigated. A sharp decrease in pore volume was observed as the temperature increased. The maximum bending strength (~45 MPa) was achieved for BCP which was mixed with 3 wt% NBG-Sr and sintered at 1200 °C. This value was approximately the same when it was sintered at 1300 °C. The bending strength failed when both lower and higher amounts of 3 wt% NBG-Sr were utilized. Therefore, sintering of composites at 1200 °C was economically reasonable. The X-ray results showed that NBG-Sr additive did not change the phase composition of BCP when it was heat treated at 1200 °C. The attachment and proliferation of rat calvarium-derived osteoblasts on samples sintered at 1200 °C were also evaluated by scanning electron microscopy (SEM). Based on cell studies, all NBG-Sr-added BCPs supported attachment and proliferation of osteoblastic cells. Overall, biphasic calcium phosphate materials with improved mechanical and biological properties can be produced by using certain quantity of strontium-containing bioactive glass particles.

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Characterization of sol-gel silica glass and its composites through study of physical and chemical properties of entrapped molecules

10.31274/rtd-180813-12127 ◽

2001 ◽

Author(s):

Jovica Dimitrije Badjić

Keyword(s):

Silica Glass ◽

Sol Gel ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Physical And Chemical ◽

And Chemical Properties

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In vitro Behaviour of Alumina-Hydroxiapatite Composites Coatings

Revista de Chimie ◽

10.37358/rc.18.6.6336 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1416-1418

Author(s):

Alexandru Szabo ◽

Ilare Bordeasu ◽

Ion Dragos Utu ◽

Ion Mitelea

Keyword(s):

Pure Titanium ◽

Titanium Substrate ◽

High Strength ◽

Biological Properties ◽

Commercially Pure Titanium ◽

Hvof Spraying ◽

Before And After ◽

Sbf Solution ◽

Oxygen Fuel

Hydroxyapatite (HA) is a very common material used for biomedical applications. Usually, in order to improve its poor mechanical properties is combined or coated with other high-strength materials.The present paper reports the manufacturing and the biocompatibility behaviour of two different biocomposite coatings consisting of alumina (Al2O3) and hydroxyapatite (HA) using the high velocity oxygen fuel (HVOF) spraying method which were deposited onto the surface of a commercially pure titanium substrate. The biological properties of the Al2O3-HA materials were evaluated by in vitro studies. The morphology of the coatings before and after their immersing in the simulated body fluid (SBF) solution was characterized by scanning electron microscopy (SEM). The results showed an important germination of the biologic hydroxyapatite crystallite on the surface of both coatings.

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Amorphous–Crystalline Calcium Phosphate Coating Promotes In Vitro Growth of Tumor-Derived Jurkat T Cells Activated by Anti-CD2/CD3/CD28 Antibodies

Materials ◽

10.3390/ma14133693 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3693

Author(s):

Yurii P. Sharkeev ◽

Ekaterina G. Komarova ◽

Valentina V. Chebodaeva ◽

Mariya B. Sedelnikova ◽

Aleksandr M. Zakharenko ◽

...

Keyword(s):

T Cells ◽

Calcium Phosphate ◽

Biological Effects ◽

Electrical Potential ◽

Biological Properties ◽

Modern Trend ◽

Calcium Phosphate Coating ◽

Jurkat T Cells ◽

Micro Arc Oxidation

A modern trend in traumatology, orthopedics, and implantology is the development of materials and coatings with an amorphous–crystalline structure that exhibits excellent biocopatibility. The structure and physico–chemical and biological properties of calcium phosphate (CaP) coatings deposited on Ti plates using the micro-arc oxidation (MAO) method under different voltages (200, 250, and 300 V) were studied. Amorphous, nanocrystalline, and microcrystalline statesof CaHPO4 and β-Ca2P2O7were observed in the coatings using TEM and XRD. The increase in MAO voltage resulted in augmentation of the surface roughness Ra from 2.5 to 6.5 µm, mass from 10 to 25 mg, thickness from 50 to 105 µm, and Ca/P ratio from 0.3 to 0.6. The electrical potential (EP) of the CaP coatings changed from −456 to −535 mV, while the zeta potential (ZP) decreased from −53 to −40 mV following an increase in the values of the MAO voltage. Numerous correlations of physical and chemical indices of CaP coatings were estimated. A decrease in the ZP magnitudes of CaP coatings deposited at 200–250 V was strongly associated with elevated hTERT expression in tumor-derived Jurkat T cells preliminarily activated with anti-CD2/CD3/CD28 antibodies and then contacted in vitro with CaP-coated samples for 14 days. In turn, in vitro survival of CD4+ subsets was enhanced, with proinflammatory cytokine secretion of activated Jurkat T cells. Thus, the applied MAO voltage allowed the regulation of the physicochemical properties of amorphous–crystalline CaP-coatings on Ti substrates to a certain extent. This method may be used as a technological mechanism to trigger the behavior of cells through contact with micro-arc CaP coatings. The possible role of negative ZP and Ca2+ as effectors of the biological effects of amorphous–crystalline CaP coatings is discussed. Micro-arc CaP coatings should be carefully tested to determine their suitability for use in patients with chronic lymphoid malignancies.

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Microalgae biomass as an alternative ingredient in cookies: Sensory, physical and chemical properties, antioxidant activity and in vitro digestibility

Algal Research ◽

10.1016/j.algal.2017.07.017 ◽

2017 ◽

Vol 26 ◽

pp. 161-171 ◽

Cited By ~ 69

Author(s):

Ana Paula Batista ◽

Alberto Niccolai ◽

Patrícia Fradinho ◽

Solange Fragoso ◽

Ivana Bursic ◽

...

Keyword(s):

Antioxidant Activity ◽

Chemical Properties ◽

In Vitro Digestibility ◽

Physical And Chemical Properties ◽

Microalgae Biomass ◽

Alternative Ingredient ◽

Physical And Chemical ◽

And Chemical Properties

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Study of Whiskers to be Used in Composite Materials

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.316.51 ◽

2021 ◽

Vol 316 ◽

pp. 51-55

Author(s):

Tamara I. Shishelova ◽

Vadim V. Fedchishin ◽

Mikhail A. Khramovskih

Keyword(s):

Mechanical Properties ◽

Composite Materials ◽

Chemical Properties ◽

High Strength ◽

Rapid Expansion ◽

Physical And Chemical Properties ◽

Reinforcement Fiber ◽

Object Of Study ◽

Physical And Chemical ◽

And Chemical Properties

Rapid expansion of technologies poses higher requirements to structural materials and items made of them. Conventional materials are being replaced by composite materials (composites). Different additives enhancing the properties of initial materials are used as reinforcement fibers of composites. Utilization of micro-and nanosize particles for production of present-day materials is paid much attention to. Whiskers are among such materials. These crystals have high strength, high chemical and temperature resistance. But for rational utilization of whickers of different chemical composition in composite materials one should know their physical and chemical properties. Objectives of the paper: to study physical and chemical properties of whiskers in different compounds, their composition and structure; to prove experimentally the feasibility of utilizing whiskers as a reinforcement fiber of composite materials. Object of study: specimens of whiskers of silicon nitride (Si3N4), aluminum oxide (Al2O3), aluminum nitride (AlN), and mullite (Al6Si2O13). Methods of investigation: thermal study of specimens, study of mechanical properties and chemical strength, and IR-spectroscopy. Results of study: specimens of whiskers have been studied and their mechanical properties have been tabulated for comparison. Extensive thermal investigation was followed by deduction of regularities and identification of chemical properties of whiskers. IR-spectra of whiskers have been studied and conclusions on molecular composition and on presence of impurities in some whiskers have been made.

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Structuring-agent role in physical and chemical properties of Mo/SiO2 catalysts by sol-gel method

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-018-4892-7 ◽

2018 ◽

Vol 89 (2) ◽

pp. 416-425

Author(s):

William Giovanni Cortés-Ortiz ◽

Alexander Baena-Novoa ◽

Carlos Alberto Guerrero-Fajardo

Keyword(s):

Sol Gel ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

Gel Method ◽

Sol Gel Method ◽

Physical And Chemical ◽

And Chemical Properties

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Infrared Characterization of PMMA-SiO2 Hybrid Glasses Obtained by Sol-Gel Process

MRS Proceedings ◽

10.1557/proc-1278-s08-13 ◽

2010 ◽

Vol 1278 ◽

Author(s):

L.L. Díaz-Flores ◽

A. S. López Rodríguez ◽

P. SifuentesGallardo ◽

M.A. Hernàndez Rivera ◽

M.a Garnica Romo ◽

...

Keyword(s):

Sol Gel ◽

Chemical Properties ◽

Hybrid Coatings ◽

Force Microscopy ◽

Air Atmosphere ◽

Atomic Force ◽

Sol Gel Process ◽

Traditional Process ◽

And Chemical Properties

AbstractThis work is about the production of hybrid coatings of the system SiO2-PMMA (PMMA, polymethylmethacrylate). These materials have interesting mechanical and chemical properties useful for anticorrosive and wear resistance applications. SiO2-PMMA hybrids were obtained by the sol-gel traditional process, using tetraethylorthosilicate (TEOS) and methylmethacrylate (MMA) by Aldrich Co, as starting reagents. The SiO2:PMMA ratio was varied from 0:1 to about 1:1 at air atmosphere deposition. The coatings were obtained on acrylic sheets and silicon wafers. A diversity of coatings with chemical composition ranging from SiO2 and PMMA to obtain the SiO2-PMMA hybrids were obtained. Infrared (IR) and atomic force microscopy (AFM), were performed to determinate structural and morphological behavior.

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