scholarly journals Understanding the Biocompatibility of Sintered Calcium Phosphate with Ratio of [Ca]/[P] = 1.50

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Feng-Lin Yen ◽  
Wei-Jen Shih ◽  
Min-Hsiung Hon ◽  
Hui-Ting Chen ◽  
I-Ming Hung ◽  
...  

Biocompatibility of sintered calcium phosphate pellets with [Ca]/[P] = 1.50 was determined in this study. Calcium pyrophosphate (CPP) phase formed on the sintered pellets immersed in a normal saline solution for 14 d at 37∘C. The intensities of hydroxyapatite (HA) reflections in the X-ray diffraction (XRD) patterns of the pellets were retrieved to as-sintered state. The pellet surface morphology shows that CPP crystallites were clearly present and make an amorphous calcium phosphate (ACP) to discriminate against become to the area of slice join together. In addition, the intensities of the CPP reflections in the XRD patterns were the highest when the pellets were immersed for 28 d. When the CPP powders were extracted from the pellets after immersion in the solution for 14 d, the viability of 3T3 cells remained above 90% for culture times from 1 to 4 d. The pellet surface morphology observed using optical microscopy showed that the cells did not adhere to the bottom of the sintered pellets when cultured for 4 d; however, some CPP phase precipitates were formed, as confirmed by XRD. In consequence, the results suggest that the sintered HA powders are good materials for use in biomedical applications because of their good biocompatibility.

2008 ◽  
Vol 396-398 ◽  
pp. 615-618
Author(s):  
Rodrigo Brandão ◽  
Fernando Pupio ◽  
Nelson Heriberto A. Camargo ◽  
E. Gemelli

The bioceramics nanostructured have made important characteristics in biomedical applications, especially the calcium phosphate ceramics. The aim of this work is synthesis and characterization of calcium phosphate and nanocomposites powders, the method of dissolution of CaO in liquid medium, precipitation and formation of bone calcium phosphate matrix, and nanocomposites by adding the solution of phosphoric acid (H3PO4). The nanocomposites powders were synthesized using as strengthening silica gel nanometer (20nm) at concentrations of 1%, 2%, 3% and 5% by volume and subjected to heat treatment to 900°C for 2 hours, seeking obtained HA (Hydroxyapatite). Later the bone matrix of calcium phosphate and nanocomposites powders were subjected from process attrition milling for 2 hours, by way of comparison. The studies characterizations were conducted through the technique of X-ray diffraction, scanning electron microscopy (SEM) and dilatometric test.


2005 ◽  
Vol 284-286 ◽  
pp. 701-704 ◽  
Author(s):  
S.A. Costa ◽  
J. Miguel Oliveira ◽  
Isabel B. Leonor ◽  
Rui L. Reis

In this study, it is shown that it is possible to prepare carboxymethyl-chitosan/Ca-P hybrids using an innovative “auto-catalytic” co-precipitation method, namely by using an acid and an oxidant bath. The X-ray diffraction (XRD) patterns evidenced the formation of crystalline calcium-phosphate precipitates when using an acid bath, while amorphous ones were obtained for those produced in the oxidant bath. The Fourier Transform Infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM/EDS) studies revealed that the extent of the polymer precipitation and formation of calcium-phosphates is directly dependent on the pH and composition of the baths. Furthermore, by conducting bioactivity tests in a simulated body fluid (SBF) followed by the SEM/EDS analysis it was possible to detect the formation of an apatite layer with a cauliflower-like morphology on the surface of hybrids prepared by the acid bath, after 7 days of immersion. These results are quite promising because they can allow for the production of bioactive and biodegradable 3D porous scaffolds to be used in bone tissue engineering applications.


2008 ◽  
Vol 55-57 ◽  
pp. 593-596 ◽  
Author(s):  
P. Inchidjuy ◽  
Supakorn Pukird ◽  
J. Nukeaw

Thin films of Nickel Phthalocyanine (NiPc) are prepared at a base pressure of 10-6 mbar using Organic Evaporator System. The films are deposited onto the glass substrate at various temperatures of 100 0C, 120 0C, 140 0C and 160 0C. Crystalline of NiPc thin films was investigated by X-ray diffraction (XRD) spectroscopy. XRD patterns exhibit to become aggravated crystalline films as monoclinic structure. Surface morphology of NiPc thin films was characterized by field emission scanning electron microscope (FE-SEM). FE-SEM micrographs indicate that fiber-like morphology of NiPc is enhanced with increasing substrate temperature. The optical absorption spectra of these thin films are measured. Present studies reveal that the Q-band of NiPc thin films appears as the change of electron energy level. Absorption spectra obtained from UV-vis of deposited NiPc are declined as the substrate temperature is risen.


2015 ◽  
Vol 1112 ◽  
pp. 458-461
Author(s):  
Kiagus Dahlan ◽  
Nur Aisyah Nuzulia

The use of bioceramics for orthopedic and dental application nowadays increases due to their good biocompatibility and osteoconductivity. β-tricalcium phosphate (β-TCP) bioceramics which have excellent biodegradation properties have been in use quite extensively. This paper reports the synthesis of β-TCP bioceramics from precipitation of calcined chicken’s eggshells and phosphoric acid (H3PO4). Chicken’s eggshells were calcined at 1000°C for 5 hours to form calcium oxide (CaO). Various molarities of CaO and H3PO4, between 0.4 M and 2.4 M, were used in this experiment with the Ca:P ratio was kept 1.5:1. After precipitation, the samples were filtered and heated at a sintering temperature of 1000°C for 7 hours. The X Ray Diffraction profile showed that the patterns were affected by the molarity. The patterns of 1.2 M CaO/0.8 M H3PO4 samples showed pure β-TCP, while those of 0.6 M CaO/0.4 M H3PO4 and 2.4 M CaO/1.6 M H3PO4 samples showed the presence of hydroxyapatite and octa calcium phosphate. These findings were also supported by Fourier transform infrared spectra. The purity of the samples shown by the atomic absorption spectroscopy resulted in Ca:P ratio of 1.48:1 which is very closed to that of standard β-TCP bioceramics.


2021 ◽  
Vol 11 (8) ◽  
pp. 1428-1437
Author(s):  
Ping Sun ◽  
Shuyi Li ◽  
Jianhua Niu ◽  
Min Yi ◽  
Weixing Xu ◽  
...  

A biphasic calcium-phosphate (CaP)-coating is a promising surface modification for functionalizing various endosseous biomaterials. However, its biomedical application is limited by its low coating yield and incorporation inefficiency. We developed a highly concentrated (4.5×) supersaturated calcium-phosphate solution (SCPS) and compared its physicochemical properties with those of 1× SCPS. One milliliter of 4.5× SCPS formed a thick (110 μm) continuous coating on a titanium disc (4×4×1 mm), compared to the thin (29 μm) 1× SCPScoating. On X-ray diffraction analysis, the 4.5× SCPS-coating had characteristic dicalcium-phosphate dehydrate and apatite peaks, in contrast to the apatite-only of 1× SCPS-coating. Under acidic condition (pH 4.5), the 4. × 5SCPS-coating released significantly less Ca2+ than the 1× SCPS-coating. FITC-bovine serum albumin incorporation in the 4.5× SCPS-coating (81.20±6.42%) was significantly higher than in the 1× SCPS-coating (21.86±1.90%). Thus, this modified coating procedure holds promise for biomedical applications.


2015 ◽  
Vol 5 (1) ◽  
pp. 46
Author(s):  
Novesar Jamarun ◽  
Lia Anggresani ◽  
Syukri Arief

 ABSTRACT Preparation of Dip-Coating Calcium Phosphate via sol-gel method using natural limestone Bukit Tui as calcium precursors and diammonium hydrogen phosphate as phosphorus precursors with sol-gel process has been investigated. Ethanol was used as solvent and DEA (diethanolamine) was used stabilizing agent. The powder were prepared by calcinated the sol at 950 oC. The products were characterized by Fourier Transform Infra Red, X-Ray Diffraction and Scanning Electron Microscopy. FTIR results showed that the vibration form was PO43-, P2O74-, O-H and CO2. XRD patterns of powder with various Ca/P mol ratio showed that the product of calcium phosphate was Ca2P2O7 and also found the hydroxyapatite Ca10(PO4)6(OH)2 in Ca/P mol ratio 1,7. SEM images of powder calcium phosphate revealed that their morphology were spheric and homogen. The coating process was done at glass substrate with coating speed 20 cm/min by calcinations at 400 oC. XRD patterns of thin layer showed that the product was Ca2P2O7 and SEM images of thin layer revealed that their morphology were bulk. Keywords: Natural limestone, calcium phosphate, hydroxyapatite, sol-gel, dip-coating


2021 ◽  
Author(s):  
Ahmed Hannora ◽  
M. M. Mostafa

Abstract Biocompatibility of Silica makes it a suitable material for biomedical applications. The main components of teeth and bones are calcium phosphate (CP). Hydroxyapatite (HA) is expected to be used in different fields not only in biomedical applications but also in agriculture as a fertilizer and pollution treatment. Various substitutions in the apatite lattice play a significant role in its properties. In the present work, Silica-50, 40, 30 and 25 mol.% Hydroxyapatite nanocomposites were prepared successfully by mechanochemical processing method. X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) indicated that silica stimulates the HA decomposition to β-tricalcium phosphate (β-TCP). XRD of heat-treated compacted sample at 1200oC confirmed β-TCP and calcium phosphate silicate phases formation. Mechanical properties decreased with decreasing HA content. Electrochemical impedance spectroscopy (EIS) results revealed that pure HA possess the highest resistivity to corrosion, while the silica/HA samples showed lower corrosion resistance. The polarization resistance increases with HA content.


2011 ◽  
Vol 110-116 ◽  
pp. 3645-3649
Author(s):  
Iis Sopyan ◽  
S. F. Adlina ◽  
S.A. Mohamad

This paper discusses the dependence of microstructure and mechanical properties of sintered biphasic calcium phosphate (BCP) on sintering temperature and compacting pressure of BCP dense bodies. BCP nanopowders were prepared via hydrothermal method using eggshell as the calcium source, followed by compaction into circular disc shape at various pressure and sintered pressureless in air at various sintering temperatures. X-ray diffraction analysis of nanopowders revealed the existences of hydroxyapatite (HA) as the main phase, with β-tricalcium phosphate (β-TCP) and calcium pyrophosphate (CPP) as the second phases. Morphological evaluation by scanning electron microscopy showed BCP exhibited uniform microstructure at low temperature and coalescence of pores and exaggerated grain growth at increasing temperature. Mechanical strength tests shown by compression strength and Vickers’ hardness test revealed an increase of strength with increasing temperature of up to 1100°C, after which it dropped. Mechanical strength also proved to be better with higher compacting pressure.


Author(s):  
R H Dixon ◽  
P Kidd ◽  
P J Goodhew

Thick relaxed InGaAs layers grown epitaxially on GaAs are potentially useful substrates for growing high indium percentage strained layers. It is important that these relaxed layers are defect free and have a good surface morphology for the subsequent growth of device structures.3μm relaxed layers of InxGa1-xAs were grown on semi - insulating GaAs substrates by Molecular Beam Epitaxy (MBE), where the indium composition ranged from x=0.1 to 1.0. The interface, bulk and surface of the layers have been examined in planar view and cross-section by Transmission Electron Microscopy (TEM). The surface morphologies have been characterised by Scanning Electron Microscopy (SEM), and the bulk lattice perfection of the layers assessed using Double Crystal X-ray Diffraction (DCXRD).The surface morphology has been found to correlate with the growth conditions, with the type of defects grown-in to the layer (e.g. stacking faults, microtwins), and with the nature and density of dislocations in the interface.


2015 ◽  
Vol 7 (1) ◽  
pp. 1346-1351
Author(s):  
Ch.Gopal Reddy ◽  
Ch. Venkateshwarlu ◽  
P. Vijaya Bhasker Reddy

Co-Zr substituted M-type hexagonal barium ferrites, with chemical formula BaCoxZrxFe12-2xO19 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), have been synthesized by double sintering ceramic method. The crystallographic properties, grain morphology and magnetic properties of these ferrites have been investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). The XRD patterns confirm the single phase with hexagonal structure of prepared ferrites. The magnetic properties have been investigated as a function of Co and Zr ion composition at an applied field in the range of 20 KOe. These studies indicate that the saturation magnetization (Ms) in the samples increases initially up to the Co-Zr composition of x=0.6 and decreases thereafter. On the other hand, the coercivity (Hc) and Remanent magnetization (Mr) are found to decrease continuously with increasing Co-Zr content. This property is most useful in permanent magnetic recording. The observed results are explained on the basis of site occupation of Co and Zr ions in the samples.


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