scholarly journals Organic/Inorganic bioactive materials Part II: in vitro bioactivity of Collagen-Calcium Phosphate Silicate/Wollastonite hybrids

2009 ◽  
Vol 7 (4) ◽  
pp. 711-720 ◽  
Author(s):  
Lachezar Radev ◽  
Vladimir Hristov ◽  
Bisserka Samuneva ◽  
Dimitrina Ivanova
Keyword(s):  
Calcium Phosphate ◽  
Sol Gel ◽  
Ceramic Powder ◽  
Red Shift ◽  
Type I ◽  
Carbonate Apatite ◽  
Bioactive Materials ◽  
Carboxylate Groups ◽  
Phosphate Silicate

AbstractIn the present study, novel hybrid materials of Collagen (C) and Calcium Phosphate Silicate/Wollastonite (CPS/W) were synthesized. The CPS/W ceramic was prepared via polystep sol-gel method. The dissolution test of CPS/W ceramic was filled with TRIS-HCl buffer. FTIR depicts that hydroxyl carbonate apatite (OHCO3HA) was observed after 3 days of immersion in TRIS-HCl buffer. Biohybrids of C-CPS/W were produced from diluted hydrochloric acid collagen type I and ceramic powder with different ratios of C and CPS/W equal to 25:75 and 75:25 wt.%. The synthesized hybrids were characterized by FTIR, XRD and SEM. FTIR depicts a “red shift” if amide I could be attributed to the fact that the collagen prefers to chelate Ca2+ from partial dissolution of CPS/W ceramic. The growth of B-type carbonate containing hydroxyapatite (B-CO3HA) on the C-CPS/W hybrids soaked in 1.5SBF was observed. The negatively charged carboxylate groups from the collagen may be responsible for hydroxyapatite (HA) deposition. This fact was confirmed by the “red shift” of carboxylate groups of collagen in FTIR spectra. The formation of HA was observed by FTIR, XRD and SEM.

scholarly journals Organic / inorganic bioactive materials Part I: Synthesis, structure and in vitro assessment of collagen/silicocarnotite biocoatings

2009 ◽  
Vol 7 (4) ◽  
pp. 702-710 ◽  
Author(s):  
Vladimir Hristov ◽  
Lachezar Radev ◽  
Bisserka Samuneva ◽  
Georgi Apostolov
Keyword(s):  
Type I Collagen ◽  
Sol Gel ◽  
Weight Ratio ◽  
Type I ◽  
Bioactive Materials ◽  
Organic Part ◽  
Carboxylate Groups ◽  
Cross Linkage ◽  
Collagen Molecules

AbstractThe silicocarnotite, as an inorganic part of the coatings, has been synthesized using a polystep sol-gel method. The chemical composition of the prepared silicocarnotite sol is described as 58.12 CaO, 29.42 P2O5, 12.45 SiO2 (wt%), where Ca/P+Si = 1,67. The acid soluble type I collagen, as an organic part of the obtained coatings, was mixed with silicocarnotite powder in a weight ratio of 25:75 and 75:25 weight ratio without cross-linkage. The acidity of the obtained mixture was readjust with 25% NH4OH to pH = 9.0. The mixture was then dried at 37°C for 12 h.The growth of B-type carbonate containing hydroxyapatite (B-type CO3HA) in which CO3 2+→PO4 3− on the surface of collagen/silicocarnotite coatings soaked in 1.5 simulated body fluid (1.5 SBF) was observed. The nucleation of B-type CO3HA was estimated on the obtained coatings after 3 days immersion in 1.5 SBF. The negatively charged carboxylate groups from the collagen surface may be responsible for the HA deposition. This was confirmed by the “red shift” of carboxylate groups of collagen molecules in the FTIR spectra. After soaking in 1.5 SBF, the morphology of prepared coatings and HA formation was observed by SEM.

scholarly journals Organic/inorganic bioactive materials part IV: In vitro assessment of bioactivity of gelatin-calcium phosphate silicate/wollastonite hybrids

2010 ◽  
Vol 8 (2) ◽  
pp. 278-284 ◽  
Author(s):  
Lachezar Radev ◽  
Vladimir Hristov ◽  
Maria Fernandes ◽  
Isabel Salvado
Keyword(s):  
Calcium Phosphate ◽  
Hybrid Materials ◽  
Red Shift ◽  
In Vitro Test ◽  
Bioactive Materials ◽  
Phosphate Silicate ◽  
Vitro Test ◽  
In Vitro Assessment

AbstractBiohybrids consisting of gelatin (G) and calcium phosphate silicate/wollastonite (CPS/W) have not been prepared so far. In this work our results are focused on the possibility of obtaining G-CPS/W bioactive hybrids in vitro. XRD, FTIR, SEM/EDS techniques were employed to characterize the synthesized hybrid materials. FTIR shows that before immersion in 1.5 SBF the “red shift” of COO- band for pure G is observed. The presence of this bond could be attributed to the formation of COO-Ca2+ via non-biomimetic route. After immersion in 1.5 SBF, FTIR shows the presence of A- and B-type carbonate containing hydroxyapatite (A/B-CO3HA). ESD and FTIR show that small amount of calcite (CaCO3) are present after in vitro test in 1.5 SBF for 3 days. XRD reveals that CO3HA and small amounts of CaCO3 can be detected after in vitro test. SEM results obtained for immersed samples show that hydroxyapatite (HA) particles fully covered the surface of the hybrids by a layer composed of spherulites. At higher magnification, very small elongated crystallites could be observed.

scholarly journals Organic/Inorganic bioactive materials Part III: in vitro bioactivity of gelatin/silicocarnotite hybrids

2009 ◽  
Vol 7 (4) ◽  
pp. 721-730 ◽  
Author(s):  
Lachezar Radev ◽  
Maria Fernandes ◽  
Isabel Salvado ◽  
Daniela Kovacheva
Keyword(s):  
Calcium Phosphate ◽  
Hybrid Materials ◽  
Calcium Phosphates ◽  
Ceramic Powder ◽  
Structure Evolution ◽  
In Vitro Test ◽  
In Vitro Bioactivity ◽  
Bioactive Materials ◽  
Vitro Test

AbstractIn this work we present our experimental results on synthesis, structure evolution and in vitro bioactivity assessment of new gelatin/silicocarnotite hybrid materials. The hybrids were obtained by diluting gelatin (G) and silicocarnotite (S) ceramic powder with G:S ratios of 75:25 and 25:75 wt.% in hot (40°C) water. The hybrids were characterized using XRD, FTIR, SEM/EDS and XPS. FTIR depicts that the “red shift” of amide I and COO− could be attributed to the fact that the gelatin prefers to chelate Ca2+ from S. The growth of calcium phosphates on the surface of the hybrids synthesized and then immersed in 1.5 SBF for 3 days was studied by using of FTIR, XRD and SEM/EDS. According to FTIR results, after an immersion of 3 days, A and B-type CO3HA can be observed on the surface. XRD results indicate the presence of hydroxyapatite with well defined crystallinity. SEM/EDS of the precipitated layers show the presence of CO3HA and amorphous calcium phosphate on the surface of samples with different G/S content when immersed in 1.5 SBF. XPS of the G/S hybrid with 25:75 wt.% proved the presence of Ca-deficient hydroxyapatite after an in vitro test for 3 days.

scholarly journals Sol-gel bioactive glass-ceramics Part I: Calcium phosphate silicate/wollastonite glass-ceramics

2009 ◽  
Vol 7 (3) ◽  
pp. 317-321 ◽  
Author(s):  
Lachezar Radev ◽  
Vladimir Hristov ◽  
Irena Michailova ◽  
Bisserka Samuneva
Keyword(s):  
Calcium Phosphate ◽  
Sol Gel ◽  
Glass Ceramics ◽  
Molar Ratio ◽  
Structure Evolution ◽  
Apatite Formation ◽  
Sol Gel Process ◽  
Phosphate Silicate ◽  
Good Agreement

AbstractIn this work we present experimental results about synthesis, structure evolution and in vitro bioactivity of new calcium phosphate silicate/wollastonite (CPS/W) glass-ceramics. The samples obtained were synthesized via polystep sol-gel process with different Ca/P+Si molar ratio (R). The structure of the materials obtained was studied by XRD, FTIR spectroscopy and SEM. XRD showed the presence of Ca15(PO4)2(SiO4)6, β-CaSiO3 and α-CaSiO3 for the sample with R=1.89 after thermal treatment at 1200°C/2h. The XRD results are in good agreement with FTIR analysis. SEM denotes that apatite formation can be observed after soaking in simulated body fluid (SBF).

Biomimetic Fabrication and Characterization of BG/COL/HCA Scaffolds for Bone Tissue Engineering

2007 ◽  
Vol 336-338 ◽  
pp. 1574-1576
Author(s):  
Xiao Feng Chen ◽  
Ying Jun Wang ◽  
Chun Rong Yang ◽  
Na Ru Zhao
Keyword(s):  
Tissue Engineering ◽  
Calcium Phosphate ◽  
Bioactive Glass ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Type I Collagen ◽  
Porous Scaffold ◽  
Sol Gel ◽  
Type I ◽  
Carbonate Apatite

The bone tissue engineering scaffold was developed by compounded the type I collagen with the porous scaffold of the sol-gel derived bioactive glass (BG) in the system CaO-P2O5-SiO2. The resultant porous scaffold was treated in supersaturated calcification solution (SCS) to form the surface layer of hydroxyl-carbonate-apatite (HCA) since the type I collagen possessed good biocompatibility and bio-absorbability, and also, the ability of inducting calcium phosphates to precipitated inside and outside the collagen fibers where the collagen fibers acted as bio-macromolecules template for formation of bone-like inorganic minerals in nature bone such as: octo-calcium phosphate (OCP), tri-calcium phosphate (TCP) and hydroxyl-carbonate-apatite (HCA). On the other hand, the sol-gel derived bioactive glass also played an important role in formation of the above bio-minerals owing to its serial chemical reactions with the body fluid. The in vitro study in supersaturated calcification solution SCS indicated that the surface of the porous scaffold was able to induce formation of bone-like HCA crystals on the pore walls of the scaffold which possessed satisfactory cells biocompatibility.

In Vitro Dissolution Behavior of Gel-Derived Bioactive Glasses in the SiO2-CaO-P2O5-MgO System

2005 ◽  
Vol 288-289 ◽  
pp. 541-544
Author(s):  
Yurong Cai ◽  
Lian Zhou ◽  
Jian Hua Wei ◽  
Zhen Tao Yu ◽  
Jin Long Niu
Keyword(s):  
Calcium Phosphate ◽  
Ph Value ◽  
Sol Gel ◽  
Glass Ceramics ◽  
Surface Characteristic ◽  
In Vitro Dissolution ◽  
Dissolution Behavior ◽  
Carbonate Apatite ◽  
High Concentration

Bioactive glass-ceramics of the SiO2-CaO-P2O5-MgO system were fabricated by sol-gel-self propagating method. Two Gel-derived materials discs， 5S and 3S， were prepared by compression of powders. The materials obtained were examined in vitro with regard to the dissolution behavior and the formation ability of calcium phosphate layer on the surfaces of samples in simulated body fluid (SBF). Concentration of ions and pH value in SBF were determined by ICP-AES and micro acidity meter after 3S and 5S were immerged in SBF for intervals from 6h to 15 days and the surface characteristic of 3S and 5S soaked were determined by SEM. Experiment results showed that the formation ability of calcium phosphate on the surface of gel-derived materials depended on the speed of dissolution of samples, which related to original chemical composition and size of crystal on the surface of materials. With decreasing of Si content and increasing of Ca content, smaller crystal could be formed on the surface of 3S, which tended to dissolve more quickly in SBF. Solubility product of calcium phosphate can be reached more easily in the solution with high concentration of Ca and P and bone-like carbonate apatite formed easily on the surface of 3S.

A Comprehensive Study of Osteogenic Calcium Phosphate Silicate Cement: Material Characterization and In Vitro/In Vivo Testing

2015 ◽  
Vol 5 (4) ◽  
pp. 457-466 ◽  
Author(s):  
Tianxing Gong ◽  
Zhiqin Wang ◽  
Yixi Zhang ◽  
Yubiao Zhang ◽  
Mingxiao Hou ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Material Characterization ◽  
Cement Material ◽  
Phosphate Silicate ◽  
In Vivo Testing ◽  
Comprehensive Study

scholarly journals Dual-Purpose Materials Based on Carbon Xerogel Microspheres (CXMs) for Delayed Release of Cannabidiol (CBD) and Subsequent Aflatoxin Removal

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3398
Author(s):  
Farid B. Cortés ◽  
Karol Zapata ◽  
Benjamín A. Rojano ◽  
Francisco Carrasco-Marín ◽  
Jaime Gallego ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Desorption Kinetics ◽  
Type I ◽  
Carbon Xerogel ◽  
Batch Mode ◽  
Dual Purpose ◽  
Delayed Release ◽  
Kinetics Of

The main objective of this study is to develop a novel dual-purpose material based on carbon xerogel microspheres (CXMs) that permits the delayed release of cannabidiol (CBD) and the removal of aflatoxin. The CXMs were prepared by the sol-gel method and functionalized with phosphoric acid (CXMP) and melamine (CXMN). The support and the modified materials were characterized by scanning electronic microscopy (SEM), N2 adsorption at −196 °C, X-ray photoelectron spectroscopy (XPS), and zeta potential. For the loading of the cannabidiol (CBD) in the porous samples, batch–mode adsorption experiments at 25 °C were performed, varying the concentration of CBD. The desorption kinetics was performed at two conditions for simulating the gastric (pH of 2.1) and intestinal (pH of 7.4) conditions at 37 °C based on in vitro CBD release. Posteriorly, the samples obtained after desorption were used to study aflatoxin removal, which was evaluated through adsorption experiments at pH = 7.4 and 37 °C. The adsorption isotherms of CBD showed a type I(b) behavior, with the adsorbed uptake being higher for the support than for the modified materials with P and N. Meanwhile, the desorption kinetics of CBD at gastric conditions indicated release values lower than 8%, and the remaining amount was desorbed at pH = 7.4 in three hours until reaching 100% based on the in vitro experiments. The results for aflatoxin showed total removal in less than 30 min for all the materials evaluated. This study opens a broader landscape in which to develop dual-purpose materials for the delayed release of CBD, improving its bioavailability and allowing aflatoxin removal in gastric conditions.

scholarly journals Bioactive calcium phosphate–based glasses and ceramics and their biomedical applications: A review

2017 ◽  
Vol 8 ◽  
pp. 204173141771917 ◽  
Author(s):  
Md Towhidul Islam ◽  
Reda M Felfel ◽  
Ensanya A Abou Neel ◽  
David M Grant ◽  
Ifty Ahmed ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Biomedical Applications ◽  
Culture Medium ◽  
Glass Ceramics ◽  
Phosphate Glasses ◽  
Bioactive Materials ◽  
Test Parameters ◽  
Phosphate Buffered Saline ◽  
Hydroxyapatite Formation

An overview of the formation of calcium phosphate under in vitro environment on the surface of a range of bioactive materials (e.g. from silicate, borate, and phosphate glasses, glass-ceramics, bioceramics to metals) based on recent literature is presented in this review. The mechanism of bone-like calcium phosphate (i.e. hydroxyapatite) formation and the test protocols that are either already in use or currently being investigated for the evaluation of the bioactivity of biomaterials are discussed. This review also highlights the effect of chemical composition and surface charge of materials, types of medium (e.g. simulated body fluid, phosphate-buffered saline and cell culture medium) and test parameters on their bioactivity performance. Finally, a brief summary of the biomedical applications of these newly formed calcium phosphate (either in the form of amorphous or apatite) is presented.

Gene Expression of C2C12 Cells on Calcium Phosphate Ceramic In Vitro

2005 ◽  
Vol 288-289 ◽  
pp. 265-268 ◽  
Author(s):  
Yan Fei Tan ◽  
Ling Li Zhang ◽  
Xin Lai He ◽  
Wei Qiang Xiao ◽  
Hong Song Fan ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Type I Collagen ◽  
C2c12 Cell ◽  
C2c12 Cells ◽  
Type I ◽  
Calcium Phosphate Ceramic ◽  
Mtt Method ◽  
Difference Expression

The osteoinduction of Calcium Phosphate (CaP) had been proved and generally been investigated by in vivo implantation. However, the mechanism of the osteoinductivity was not clear and it was difficult to judge the osteoinductivity in vitro. In this study, Mouse C2C12 cell line, a kind of myoblast precursor cell, was employed to co-culture with CaP. The induction of cell differentiation by materials was tested by MTT method, fluorescence observation, especially the mRNA expression of Osteocalcin, Type I collagen and Fibronectin by RT-PCR. It was founded that C2C12 cells could be induced to expression osteocalcin when growth on the surface of the HA/TCP ceramics. At the same time, the ceramics with different composition and sintering temperature seemed to induce difference expression level of the related genes. The results proved that phase composition was one of the most important factors in the regulation of bone-related genes. This study provided a potential model to evaluate the osteoinductivity of CaP ceramics in vitro.

Sign in / Sign up

Export Citation Format

Share Document