Synthesis and Characterization of Three Hydrated Calcium Phosphates Used as Biocement Precursors

2014 ◽  
Vol 936 ◽  
pp. 712-716 ◽  
Author(s):  
Priscila Ferraz Franczak ◽  
Nelson Heriberto Almeida Camargo ◽  
Nelson Levandowski ◽  
Daiara Floriano da Silva

Calcium phosphates biocements are biomaterials that present crystallographic and mineralogical characteristics similar to human skeletal structure. This has led to the development of new calcium phosphates biomaterials for biomedical applications, especially biomaterials for repairing defects and bone reconstruction. Calcium phosphates biocements are a promising alternative in biomedical applications, for they are easy to mold, they have good wettability, hydration and hardening capacity during its application in biological environment. This work aimed at the synthesis of hydrated calcium phosphates powder, precursor to late biocements development. Three calcium phosphates compositions were produced via CaCO3/phosphoric acid reactive method in the ratios Ca/P = 1,5; 1,6 e 1,67 molar. The presented results are associated to hydrated powder morphology and synthesis process control. Field Electronic Microscope helped with the morphological characterization of the powders, Fourier Transformed Infrared Spectroscopy (FTIR) gave support to the identification of H2O e PO43- grouping vibrational bands and x-ray diffractometry (XRD) served on crystallographic characterization of hydrated calcium phosphates. The work showed that for the different powder compositions the hydrated calcium phosphate phase is formed by clustered fine particles. This demonstrated that the chosen synthesis method permits the obtaining nanoparticles of hydrated calcium phosphates, precursors for later biocement production.

2014 ◽  
Vol 798-799 ◽  
pp. 443-448
Author(s):  
Priscila Ferraz Franczak ◽  
Nelson Heriberto Almeida Camargo ◽  
Pricyla Corrêa ◽  
Enori Gemelli

Calcium phosphates biocements are biomaterials that present crystallographic and mineralogical characteristics similar to human skeletal structure. This has led to the development of new calcium phosphates biomaterials for biomedical applications, especially biomaterials for repairing defects and bone reconstruction. Calcium phosphates biocements are a promising alternative in biomedical applications, for they are easy to mold, they have good wettability, hydration and hardening capacity during its application in biological means. This work aimed at the synthesis of hydrated calcium phosphates powder, through a simple reactive method, which will be the basis for the production of calcium phosphate biocimentos with self-setting reaction. Three calcium phosphates compositions were produced via CaCO3/phosphoric acid reactive method in the ratios Ca/P = 1,5; 1,6 e 1,67 molar. The presented results are associated to hydrated powder morphology and synthesis process control. Scanning Electron Microscopy (SEM) helped with the morphological characterization of the powders, the laser analysis method was used for determining particle size and the Fourier Transformed Infrared Spectroscopy (FTIR) gave support to the identification of H2O e PO43-grouping vibrational bands. The work showed that for the different powder compositions the hydrated calcium phosphate phase is formed by clustered fine particles. This demonstrated that the chosen synthesis method permits the obtention of hydrated calcium phosphates, precursors for later biocement production.


2016 ◽  
Vol 881 ◽  
pp. 159-164
Author(s):  
Maicon Douglas Possamai ◽  
Nelson Heriberto Almeida Camargo ◽  
Daiara Floriano-Silva ◽  
Marli Baltazar Roesler Eckstein ◽  
Priscila Ferraz Franczak

Bone reconstruction biomaterials are topics of interest in dentistry, orthopedics, scientific, commercial. The most popular bone repairing and reconstruction biomaterials are calcium phosphates. The demand for biomaterials is associated with the chemical and crystallographic characteristics of the human bone apatite. The wet synthesis method is common in the production of nanostructured powders of hydrated calcium phosphates, providing nanoparticles with sizes less than 50nm. This study aimed to synthesize and characterize hydrated calcium phosphate powders in the molar ratio of Ca/P = 1.67. After calcination at temperature 900°C/2h, these powders provide nanostructured hydroxyapatite matrix. The characterization studies were performed with Scanning Electron Microscopy, X-rays diffraction and Infrared Spectroscopy by Fourier Transform. The results show that the synthesis method provides hydrated calcium phosphate powders formed by aggregated and agglomerated nanoparticles. The thermal treatment of hydrated calcium phosphate powder led to formation of hydroxyapatite matrix.


2007 ◽  
Vol 12 (4) ◽  
pp. 574-582 ◽  
Author(s):  
Nelson Heriberto de Almeida Camargo ◽  
O. J. Bellini ◽  
Enori Gemelli ◽  
M. Tomiyama

Nanostructured materials have been largely studied in the last few years because they have a great potential to applications in different fields like physics, chemistry, biology, mechanic and medicine. Synthesis and characterization of nanostructured materials is a subject of great interest involving science, market, politicians, government and society. The nanostructured materials are in demand in biomedical area, mainly the bioceramics composed of calcium phosphates (Ca/P), which have an excellent biocompatibility and mineralogical characteristics similar to those of bones. The aim of this work was to optimize the method of powder synthesis of nanostructured calcium phosphate and of nanocomposites composed of calcium phosphate//SiO2n, containing 5, 10 and 15% (in volume) of nanometric silica (SiO2n). The results are expressed according to the method of synthesis, mineralogical and morphological characterization, and thermal behavior for the different compositions of the nanostructured powder synthesized.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Negin Mohammadi ◽  
Zahra Khakpour ◽  
Amir Maghsoudipour ◽  
Aida Faeghinia

The perovskite Lanthanum Strontium Cobalt Ferrite (LSCF) is investigated as the cathode material used in intermediate-temperature solid oxide fuel cells (IT-SOFCs). In the present study, La0.6−xDyxSr0.4Co0.2Fe0.8O3−δ (x = 0, 0.3, 0.6) was synthesized through the coprecipitation method. The obtained precipitate was calcined at 500, 700, 900, and 1000°С. Phase characterization of the synthesized LSCF and LDySCF powder before and after heat treatment at 700°С was carried out by X-ray diffraction (XRD) analysis. XRD patterns revealed that the perovskite phase was obtained at 700°С in all calcined samples. Chemical bond study to investigate the synthesis process was conducted using the Fourier transform infrared spectroscopy technique. Thermal analysis of DTA and TG has been utilized to investigate how the calcination temperature affects the perovskite phase formation. According to the STA results, the perovskite phase formation started at 551°С and completed at 700°С. The density values of synthesized powders were 6.10, 6.11, and 6.37 g·cm−3for the undoped and doped samples calcined at 700°С. Powder morphology was studied by field emission scanning electron microscopy (FE-SEM). The micrographs showed the spherical-shaped particles with the average particle size of 24–131 nm.


2018 ◽  
Vol 226 ◽  
pp. 03011
Author(s):  
Elizaveta A. Mukhanova ◽  
Vyacheslav G. Vetokhin ◽  
Alexander A. Rybalkin

Various modifications of Ge-substituted calcium phosphates were obtained using solid-phase synthesis, co-precipitation in solution, and combustion synthesis. Structural changes in the synthesis process are established using X-ray diffraction. The biological activity of the obtained samples in model fluids was estimated. It has been found that the synthesis method can lead to various structural modifications of calcium phosphate, which is a significant refinement to the phase diagram of the Ca3(PO4)2- Ca2GeO4 system described in the literature.


2017 ◽  
Vol 25 (1) ◽  
pp. 23-26
Author(s):  
Tran Hoang Hai ◽  
Le Hong Phuc ◽  
Doan Thi Kim Dung ◽  
Nguyen Thi Le Huyen ◽  
Bui Duc Long ◽  
...  

The ferrite (a Fe3O4 – gFe2O3 mixed solution) fine particles, ~8 nm in size were synthesized from an aqueous solution. Trypsin, a proteolytic enzyme or a protein, was immobilized onto the surfaces of those particles during the synthesis process. The process was performed in the open air at a temperature as low as 4°C and on near-neutral condition of pH = 9, which is compatible with most of the bioactive molecules as well as trypsin. Therefore this technique is advantageous for preparing magnetite particles having biomolecules immobilized on their surfaces, which will be used for biomedical applications utilizing magnetic separation technique.


2016 ◽  
Vol 869 ◽  
pp. 884-889
Author(s):  
Nadia Sueli Vieira Capanema ◽  
Alexandra A.P. Mansur ◽  
Herman Sander Mansur

The need for obtaining new materials to replace human body parts that were destroyed or damaged led scientists from different areas of research for developing new biomaterials. Thus, the aim of this work was the synthesis and characterization of niobium-modified apatite bioceramics. Calcium phosphates (CaP) were synthesized with niobium partially replacing calcium sites using aqueous precipitation route at room temperature. The bioceramics, with and without Nb incorporation, were characterized by scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) as prepared and after heat treatments The results indicated that Nb was incorporated in the apatite structure promoting morphological and structural changes in the ceramic properties.


2016 ◽  
Vol 881 ◽  
pp. 165-170
Author(s):  
Priscila Ferraz Franczak ◽  
Nelson Heriberto Almeida Camargo ◽  
Daiara Floriano-Silva ◽  
Marli Baltazar Roesler Eckstein ◽  
Maicon Douglas Possamai

The calcium phosphate bioceramics are characterized by chemical and crystallographic similarity with the human skeleton. The wet synthesis method was used in the preparation of hydrated calcium phosphate nanostructured powders and biphasic compositions of calcium phosphate matrix. This study aimed the synthesis and characterization of a hydrated calcium phosphate matrix in the ratio Ca/P 1.67 molar and two biphasic compositions of hydrated calcium phosphate matrix, with 1% MgO and 5% α-Al2O3. Scanning Electron Microscopy (SEM) helped with the powders morphological characterization, X-ray diffractometry (XRD) served for crystallographic characterization of powders and Fourier Transformed Infrared Spectroscopy (FTIR) gave support to the identification of H2O, CO32- and PO43- grouping vibrational bands. The work showed that the presence of 1% MgO inside the hydrated calcium phosphate matrix provided brushite formation and the presence of 5% α-Al2O3 in the matrix provided the hydrated calcium phosphate powder.


2020 ◽  
Author(s):  
Negin Mohammadi ◽  
Zahra Khakpour ◽  
Amir Maghsoudipour ◽  
Aida Faeghinia

Abstract The perovskite Lanthanum Strontium Cobalt Ferrite (LSCF) is investigated as the cathode material used in intermediate temperature solid oxide fuel cells (IT-SOFCs). In the present study, La0.6-xDyxSr0.4Co0.2Fe0.8O3-δ(x= 0, 0.3, 0.6) was synthesized through co precipitation method. The obtained precipitate was calcined at500, 700,900and 1000°С. Phase characterization of synthesized LSCF and LDySCF powder before and after heat treatment at 700°Сwas carried out by X-ray diffraction (XRD) analysis. XRD patterns revealed that the perovskite phase was obtained at 700 °С in all calcined samples. Chemical bond study to investigate synthesis process was done using the Fourier transform infrared spectroscopy technique. Thermalanalysis of DTA and TG has been utilized to investigate how the calcination temperature affects the peroveskite phase formation. According to the STA results, the perovskite phase formation started at 551°Сafterwarditcompleted at 700°С.The density values of synthesized powders were 6.10, 6.11 and 6.37g.cm-3for the undoped and doped samples calcined at 700°С. Powder morphology was studied by Field emission scanning electron microscopy. (FE-SEM) micrographs showed the spherical shaped particles with the average particle size of 24-131nm.


Author(s):  
X. Lin ◽  
X. K. Wang ◽  
V. P. Dravid ◽  
J. B. Ketterson ◽  
R. P. H. Chang

For small curvatures of a graphitic sheet, carbon atoms can maintain their preferred sp2 bonding while allowing the sheet to have various three-dimensional geometries, which may have exotic structural and electronic properties. In addition the fivefold rings will lead to a positive Gaussian curvature in the hexagonal network, and the sevenfold rings cause a negative one. By combining these sevenfold and fivefold rings with sixfold rings, it is possible to construct complicated carbon sp2 networks. Because it is much easier to introduce pentagons and heptagons into the single-layer hexagonal network than into the multilayer network, the complicated morphologies would be more common in the single-layer graphite structures. In this contribution, we report the observation and characterization of a new material of monolayer graphitic structure by electron diffraction, HREM, EELS.The synthesis process used in this study is reported early. We utilized a composite anode of graphite and copper for arc evaporation in helium.


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