Properties of Calcium Phosphate Powder Prepared from Phosphoryl Oligosaccharides of Calcium

2006 ◽  
Vol 309-311 ◽  
pp. 515-518 ◽  
Author(s):  
Tomohiro Umeda ◽  
Kiyoshi Itatani ◽  
Hiroko Mochizuki ◽  
Ian J. Davies ◽  
Yoshiro Musha ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcium Ions ◽  
Dilute Hydrochloric Acid ◽  
Potato Starch ◽  
Carbonate Apatite ◽  
X Ray Diffraction ◽  
Phosphate Powder ◽  
X Ray ◽  
Calcium Phosphate Particles ◽  
Living Bone

The phosphoryl oligosaccharides of calcium (POC), extracted from potato starch, are composed of phosphorus oligosaccharides and calcium ions. Ultrafine calcium phosphate particles, whose main phase was hydroxyapatite (Ca10(PO4)6(OH)2: HAp), could be prepared through the hydrothermal treatment of POC solution at a temperature between 110 and 130°C; X-ray diffraction indicated the crystallinity of HAp in the resulting powder to be poor and similar to that of living bone. The present HAp powder was regarded to be calcium deficient carbonate apatite with the OH- group being partly substituted by a carbonate (CO3 2-) group. The solubility of the resulting powder in dilute hydrochloric acid was higher compared to that of commercially available HAp, suggesting excellent bioabsorbability for the present powder.

Fabrication of Microporous Apatite Coating on Titanium by a Novel Chemical Method

2005 ◽  
Vol 284-286 ◽  
pp. 231-234
Author(s):  
Bo Feng ◽  
Jie Weng ◽  
Shao Xing Qu ◽  
Xing Dong Zhang
Keyword(s):  
Calcium Phosphate ◽  
Photoelectron Spectroscopy ◽  
Chemical Method ◽  
Carbonate Apatite ◽  
X Ray Diffraction ◽  
Energy Dispersion Spectroscopy ◽  
X Ray ◽  
Composition And Structure ◽  
Microporous Coating ◽  
Apatite Coating

A microporous apatite coating was fabricated by a heat-oxidation and chemical routine. The morphology, composition and structure were characterized by scanning electron microscopy with X-ray energy dispersion spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The components of the coating were predominantly apatite, next tri-calcium phosphate and octa-calcium phosphate. The pore size ranged from 1µm to5µm. The thickness of the coating was about 6µm ~ 10µm. The microporous coating was Ca-deficient carbonate apatite.

scholarly journals Microwave-Assisted Fabrication of Mesoporous Silica-Calcium Phosphate Composites for Dental Application

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 53
Author(s):  
Adrian Szewczyk ◽  
Adrianna Skwira ◽  
Marta Ginter ◽  
Donata Tajer ◽  
Magdalena Prokopowicz
Keyword(s):  
Calcium Phosphate ◽  
Mesoporous Silica ◽  
Octacalcium Phosphate ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Coating Solution ◽  
X Ray ◽  
Microwave Assisted ◽  
Calcium Orthophosphates ◽  
Different Types

Herein, the microwave-assisted wet precipitation method was used to obtain materials consisting of mesoporous silica (SBA-15) and calcium orthophosphates (CaP). Composites were prepared through immersion of mesoporous silica in different calcification coating solutions and then exposed to microwave radiation. The composites were characterized in terms of molecular structure, crystallinity, morphology, chemical composition, and mineralization potential by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX). The application of microwave irradiation resulted in the formation of different types of calcium orthophosphates such as calcium deficient hydroxyapatite (CDHA), octacalcium phosphate (OCP), and amorphous calcium phosphate (ACP) on the SBA-15 surface, depending on the type of coating solution. The composites for which the progressive formation of hydroxyapatite during incubation in simulated body fluid was observed were further used in the production of final pharmaceutical forms: membranes, granules, and pellets. All of the obtained pharmaceutical forms preserved mineralization properties.

The Relative Merits of Oxides of Hafnium, Cerium and Thorium as Surrogates for Plutonium Oxide in Calcium Phosphate Ceramics

2009 ◽  
Vol 1193 ◽  
Author(s):  
B. L. Metcalfe ◽  
S. K. Fong ◽  
L. A. Gerrard ◽  
I. W. Donald ◽  
E. S. Welch ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcination Temperature ◽  
Cerium Oxide ◽  
Absorption Spectroscopy ◽  
Hafnium Oxide ◽  
Intermediate Level ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Absorption ◽  
Additional Phase

AbstractThe choice of surrogate for plutonium oxide for use during the initial stages of research into the immobilization of intermediate level pyrochemical wastes containing plutonium andamericium oxides in a calcium phosphate host has been investigated by powder X-ray diffraction and X-ray absorption spectroscopy. Two non-radioactive surrogates, hafnium oxide and cerium oxide, together with radioactive thorium oxide were compared. Similarities in behaviour were observed for all three surrogates when calcined at the lowest temperature, 750°C but differences became more pronounced as the calcination temperature was increased to 950°C. Although some reaction occurred between all the surrogates and the host to form a substituted whitlockite phase, increasing the temperature led to a significant increase in the cerium reaction and the formation of an additional phase, monazite. Additionally it was observed that the cerium became increasingly trivalent at higher temperatures.

Fabrication and evaluation of calcium phosphate cement scaffold with controlled internal channel architecture and complex shape

2007 ◽  
Vol 221 (8) ◽  
pp. 951-958 ◽  
Author(s):  
X Li ◽  
D Li ◽  
B Lu ◽  
L Wang ◽  
Z Wang
Keyword(s):  
Tissue Engineering ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Complex Shape ◽  
X Ray Diffraction ◽  
X Ray ◽  
Precise Control ◽  
Internal Channel ◽  
Channel Architecture

The ability to have precise control over internal channel architecture, porosity, and external shape is essential for tissue engineering. The feasibility of using indirect stereo-lithography (SL) to produce scaffolds from calcium phosphate cement materials for bone tissue engineering has been investigated. The internal channel architecture of the scaffolds was created by removal of the negative resin moulds made with SL. Scanning electron microscopy (SEM) showed highly open, well-interconnected channel architecture. The X-ray diffraction examination revealed that the hydroxyapatite phase formed at room temperature in the cement was basically stable up to 850 °C. There was no phase decomposition of hydroxyapatite, although the crystallinity and grain size were different. The ability of resulting structure to support osteoblastic cells culture was tested in vitro. Cells were evenly distributed on exterior surfaces and grew into the internal channels of scaffolds. To exploit the ability of this technique, anatomically shaped femoral supracondylar scaffolds with 300-800 μm interconnected channels were produced and characterized.

Synthesis of Alpha-Tricalcium Phosphate by Wet Reaction and Evaluation of Mechanical Properties

2012 ◽  
Vol 727-728 ◽  
pp. 1164-1169 ◽  
Author(s):  
Mônica Beatriz Thürmer ◽  
Rafaela Silveira Vieira ◽  
Juliana Machado Fernandes ◽  
Wilbur Trajano Guerin Coelho ◽  
Luis Alberto Santos
Keyword(s):  
Mechanical Properties ◽  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Calcium Nitrate ◽  
Chemical Precipitation ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcium Phosphate Cements

Calcium phosphate cements have bioactivity and osteoconductivity and can be molded and replace portions of bone tissue. The aim of this work was to study the obtainment of α-tricalcium phosphate, the main phase of calcium phosphate cement, by wet reaction from calcium nitrate and phosphoric acid. There are no reports about α-tricalcium phosphate obtained by this method. Two routes of chemical precipitation were evaluated and the use of two calcinations temperatures to obtain the phase of cement. The influence of calcination temperature on the mechanical properties of cement was evaluated. Cement samples were characterized by particle size analysis, X-ray diffraction, mechanical strength and scanning electron microscopy. The results demonstrate the strong influence of synthesis route on the crystalline phases of cement and the influence of concentration of reactants on the product of the reaction, as well as, on the mechanical properties of cement.

Study on Synthesis of Calcium Phosphate Biomaterials Containing SMB

2007 ◽  
Vol 330-332 ◽  
pp. 1033-1036 ◽  
Author(s):  
M.H. Li ◽  
Shu Xin Qu ◽  
R. Shen ◽  
N. Yao ◽  
P.D. Ren ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Salvia Miltiorrhiza ◽  
Reaction System ◽  
Absorption Peak ◽  
X Ray Diffraction ◽  
Wet Chemical Method ◽  
Obvious Effect ◽  
X Ray ◽  
Wet Chemical ◽  
Wet Synthesis

Calcium phosphate (CaP) biomaterials containing Chinese medicine, Danshen (Salvia Miltiorrhiza Bunge, SMB), have been synthesized in our previous study via the wet chemical method. However, CaP biomaterials were generally synthesized in the alkaline solution. The purpose of the present study was to investigate the effect of pH on SMB and the influence of SMB on the synthesis of CaP biomaterials. The SMB solutions of different pH from 5.0 to 10.0, were scanned with the UV-VIS spectrophotometer (UV-VIS) in the wavelength ranged from 200.00 to 400.00 nm. CaP biomaterials containing SMB were synthesized from (NH4)2HPO4, Ca(NO3)2, NH4OH and SMB. The filtrates of the wet synthesis of CaP biomaterials containing SMB were measured by UV-VIS. The synthesized CaP biomaterials containing SMB were characterized by the X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The results showed that the maximum absorption peak appeared at 281.00 nm for solutions of pH 5.0, 6.0 and 7.0. Although there were a new absorption peaks as the pH were 8.0 and 9.0, the absorption curves of SMB became similar to that of SMB as pH at 7.0 after the pH were readjusted to 7.0. The absorption peak appeared an Einstein shift to 347.00 nm at pH 10.0, which did not return to 281.00 nm when the pH of SMB solution was readjusted to 7.0. The absorption peak of filtrates containing SMB of CaP biomaterials reaction system was still at 281.00 nm when their pH was 7.0 and 8.0. Moreover, SMB had no obvious effect on the phase component and functional groups of products. Hence, it could be predicted that calcium phosphate biomaterials containing SMB, such as DCPD and TCP containing SMB, which could be prepared at the pH ranged from 5.0 to 9.0.

Improvement of Anti-Washout Performance of Calcium Phosphate Cement Using Modified Starch

2007 ◽  
Vol 336-338 ◽  
pp. 1628-1631 ◽  
Author(s):  
Ling Chen ◽  
Hong Xiang ◽  
Xiao Xi Li ◽  
Jian Dong Ye ◽  
Xiu Peng Wang ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Body Fluid ◽  
Clinical Applications ◽  
Modified Starch ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcium Phosphate Cements ◽  
Modified Starches ◽  
Gelatinized Starch ◽  
Bone Repairing

Calcium phosphate cements (CPCs) are well-known orthopedic materials for filling bone. However, CPC pastes tend to disintegrate immediately when contacting with blood or other aqueous (body) fluids, which is a main limitation of its clinical applications in bone repairing, reconstruction and augmentation. To improve the anti-washout performance of CPC, modified starches such as pre-gelatinized starch, etherified starch, and esterified starch were added to the liquid phase of CPC in this work. CPC with good anti-washout performance was prepared and the effects of the modified starches on the properties of CPC were investigated. The results showed that the CPC with the modified starches were more stable in simulated body fluid than that without modified starch, especially the CPC with the etherified starch (II). X-ray diffraction analysis revealed that the modified starches did not inhibit CPC components from converting to hydroxyapatite. Furthermore, the anti-washout mechanism of the modified starches in CPC was discussed. It is concluded that the addition of the modified starches such as pre-gelatinized starch, etherified starch, and esterified starch to CPC can improve its anti-washout performance and should be of value in clinical surgery where the cement is exposed to blood.

Effect of Different Solutions on Hydrothermal Treatment of β-Tricalcium Phosphate Scaffold

2017 ◽  
Vol 264 ◽  
pp. 66-69
Author(s):  
Fadilah Darus ◽  
Mariatti Jaafar
Keyword(s):  
Hydrothermal Treatment ◽  
Sodium Hydrogen Carbonate ◽  
Surface Characteristics ◽  
Carbonate Apatite ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Sodium Hydrogen ◽  
Hydrogen Carbonate ◽  
Before And After

Carbonate apatite would be ideal for bone substitute due to its composition of 4-8% carbonate similar to bone mineral. The purpose of the present study was to produce carbonate apatite scaffold by using hydrothermal treatment of β-TCP scaffold as a precursor. The effect of different solutions on hydrothermal treatment was studied. The microstructure of scaffold before and after hydrothermal were characterized by scanning electron microscopy (SEM). It is observed that surface characteristics are governed by the types of immersion solution. The typical smooth surface of the β-TCP scaffold was observed before hydrothermal. Different morphology was observed after hydrothermal in different solutions. X-Ray Diffraction (XRD) pattern indicates that the peak of apatite with low intensities present after hydrothermal treatment in sodium hydrogen carbonate solution.

Bioinspired synthesis of self-assembled calcium phosphate nanocomposites using block copolymer-peptide conjugates

2008 ◽  
Vol 23 (12) ◽  
pp. 3196-3212 ◽  
Author(s):  
Yusuf Yusufoglu ◽  
Yanyan Hu ◽  
Mathumai Kanapathipillai ◽  
Matthew Kramer ◽  
Yunus E. Kalay ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Calcium Phosphate ◽  
Small Angle ◽  
Polymer Chains ◽  
X Ray Diffraction ◽  
X Ray ◽  
Self Assembling ◽  
Transmission Electron ◽  
Angle Scattering ◽  
Inorganic Content

Thermoreversibly gelling block copolymers conjugated to hydroxyapatite-nucleating peptides were used to template the growth of inorganic calcium phosphate in aqueous solutions. Nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), transmission electron microscopy, x-ray diffraction, and small-angle scattering were used to characterize these samples and confirm that the peptides promoted the growth of hydroxyapatite as the inorganic phase. Three different polymer templates were used with varying charges on the polymer chains (nonionic, anionic, and zwitterionic), to investigate the role of charge on mineralization. All of the polymer-inorganic solutions exhibited thermoreversible gelation above room temperature. Nanocomposite formation was confirmed by solid-state NMR, and several methods identified the inorganic component as hydroxyapatite. Small angle x-ray scattering and electron microscopy showed thin, elongated crystallites. Thermogravimetric analysis showed an inorganic content of 30–45 wt% (based on the mass of the dried gel at ∼200 °C) in the various samples. Our work offers routes for bioinspired bottom-up approaches for the development of novel, self-assembling, injectable nanocomposite biomaterials for potential orthopedic applications.

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