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Journal articles on the topic 'Apatite calcium'

Author: Grafiati

Published: 28 May 2022

Last updated: 31 July 2025

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1

Soumia, Belouafa. "Oxygenated Apatites: Effect of Calcium Salt Nature and Synthesis Parameters." Der Pharma Chemica 14, no. 4 (2022): 8. https://doi.org/10.4172/0975-413X.14.4. 26-33.

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Apatitic calcium phosphates, reported in this study, are prepared following a precipitation reaction between phosphoric acid (H3PO4) and a calcium salt. Used salts are calcium carbonate (CaCO3), calcium nitrate (Ca(NO3)2) and calcium chloride (CaCl2). The variation in the chemical composition and crystallinity of oxygenated apatites, carbonated or not, depending on the nature of the reagents and the synthesis parameters was studied by X-ray diffraction, infrared spectroscopy and by chemical analysis. The insertion of molecular oxygen into the apatite tunnel is achieved through the use of hydro

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2

Belouafa, Soumia, Hassan Chaair, and Khalid Digua. "Oxygenated Apatites: Effect of Calcium Salt Nature and Synthesis Parameters." Der Pharma Chemica 14, no. 4 (2022): 8. https://doi.org/10.5281/zenodo.13354658.

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Apatitic calcium phosphates, reported in this study, are prepared following a precipitation reaction between phosphoric acid (H3PO4) and a calcium salt. Used salts are calcium carbonate (CaCO3), calcium nitrate (Ca(NO3)2) and calcium chloride (CaCl2). The variation in the chemical composition and crystallinity of oxygenated apatites, carbonated or not, depending on the nature of the reagents and the synthesis parameters was studied by X-ray diffraction, infrared spectroscopy and by chemical analysis. The insertion of molecular oxygen into the apatite tunnel is achieved through the use of hydro

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3

Kunio, Ishikawa, Shigeki Matsuya, Yumiko Suzuki, Koh-ichi Udoh, Masaharu Nakagawa, and Kiyoshi Koyano. "Fabrication of Apatite Monolith from Calcium Sulphate." Key Engineering Materials 288-289 (June 2005): 533–36. http://dx.doi.org/10.4028/www.scientific.net/kem.288-289.533.

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Present study evaluated the feasibility of apatite monolith preparation from calcium sulfate monolith using ammonium phosphate solution. We found that calcium phosphate monolith transforms to apatitic monolith without changing its original morphology when a proper temperature and a proper phosphate solution was selected. Prepared apatite was B-type carbonate apatite with low crystallinity. Although mechanical strength of the apatite monolith was lower than original calcium sulphate monolith, we concluded present method may be useful for the fabrication of apatite monolith since we can prepare

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4

Drouet, Christophe. "Apatite Formation: Why It May Not Work as Planned, and How to Conclusively Identify Apatite Compounds." BioMed Research International 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/490946.

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Calcium phosphate apatites are inorganic compounds encountered in many different mineralized tissues. Bone mineral, for example, is constituted of nanocrystalline nonstoichiometric apatite, and the production of “analogs” through a variety of methods is frequently reported. In another context, the ability of solid surfaces to favor the nucleation and growth of “bone-like” apatite upon immersion in supersaturated fluids such as SFB is commonly used as one evaluation index of the “bioactivity” of such surfaces. Yet, the compounds or deposits obtained are not always thoroughly characterized, and

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5

Rhilassi, Abdelhadi El, and Mounia Bennani-Ziatni. "Experimental study on the interaction of insulin with apatitic calcium phosphates analogous to bone mineral: adsorption and release." Current Chemistry Letters 11, no. 4 (2022): 341–52. http://dx.doi.org/10.5267/j.ccl.2022.6.003.

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The present work investigated the interaction of human insulin with synthesized poorly crystalline apatitic calcium phosphates containing simultaneously HPO42- and CO32- ions in various amount. The adsorption kinetics is very fast, while the release kinetics is generally slow. The chemical composition of apatite has an influence on both the adsorption and release processes. The experimental results show that the percentage of insulin adsorption and release decreased with the increase of the content of carbonate. The equilibrium adsorption data are fitted into Langmuir, Freundlich, Elovich, Tem

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6

Johnsson, Mats S. A., and George H. Nancollas. "The Role of Brushite and Octacalcium Phosphate in Apatite Formation." Critical Reviews in Oral Biology & Medicine 3, no. 1 (1992): 61–82. http://dx.doi.org/10.1177/10454411920030010601.

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Studies of apatite mineral formation are complicated by the possibility of forming several calcium phosphate phases. The least soluble, hydroxyapatite (HAP), is preferentially formed under neutral or basic conditions. In more acidic solutions phases such as dicalcium phosphate dihydrate (Brushite, DCPD) and octacalcium phosphate (OCP) are often found. Even under ideal HAP precipitation conditions the precipitates are generally nonstoichiometric, suggesting the formation of calcium-deficient apatites. Both DCPD and OCP havea been implicated as possible precursors to the formation of apatite. Th

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7

Rodríguez-Lorenzo, Luis M., Blanca Vázquez, and Julio San Román. "Surface Modification of Calcium Hydroxyfluor Carbonate Apatites by Bisphosphonates." Key Engineering Materials 284-286 (April 2005): 357–60. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.357.

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Hydroxyapatite has been frequently described as an osteoconductive but not osteoinductive material based on failure to observe bone formation in nonbony sites. Bisphosphonates (BPs) are stable pyrophosphate analogs, that enhance the proliferation, differentiation and bone forming activity of osteoblasts and are potent inhibitors of bone resorption. In this paper, the modification of a calcium hydroxyfluor carbonate apatite with sodium alendronate and (4-(aminomethyl)benzene)bisphosphonic acid is described. The surface modification is carried out by refluxing the apatite in a bisphosphonate ace

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8

Shimoda, S., T. Aoba, E. C. Moreno, and Y. Miake. "Effect of Solution Composition on Morphological and Structural Features of Carbonated Calcium Apatites." Journal of Dental Research 69, no. 11 (1990): 1731–40. http://dx.doi.org/10.1177/00220345900690110501.

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The composition of enamel mineral corresponds to that of a calcium carbonato-apatite. For insight to be gained into the precipitation of carbonato-apatites having specific properties (crystal size, morphology, and carbonate incorporation into the crystal lattice), apatites were prepared at 80°C in aqueous systems having various CO3 concentrations and pH values of around 7.5 or 10.5 (± 0.5). The various preparations had a wide range (0.005 to 0.19) of CO3/Ca molar ratios that bracket the ratios found in porcine enamel mineral at various developmental stages. Fourier transform infrared spectrosc

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9

Soroka, A. P., I. V. Suhenko, V. H. Kasianenko, V. L. Karbivskii, L. I. Karbivska, and S. S. Smolyak. "Electronic structure of calcium and cadmium arsenate apatites." Low Temperature Physics 51, no. 3 (2025): 375–83. https://doi.org/10.1063/10.0035843.

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The electronic structure of a wide range of apatite compounds Me10(AsO4)6X2, where Me = Ca and Cd, X = F, Cl, OH, and Br, has been calculated using first principles within the framework of density functional theory. This was achieved via the full-potential all-electron augment plane wave (APW) method with a set of basis functions with the addition of local orbitals (APW + lo). The study established the effects of changes in spatial charge distributions and the energy structure of valence and conduction bands for apatites in the specified series. Bader charge analysis was performed to clarify t

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10

Ingram, G. S., and W. M. Edgar. "Calcium Salt Precipitation and Mechanisms of Inhibition Under Oral Conditions." Advances in Dental Research 9, no. 4 (1995): 427–32. http://dx.doi.org/10.1177/08959374950090041301.

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Dental calculus contains a range of calcium phosphates, derived from plaque fluid and the saliva. Older deposits tend to contain more hydroxyapatite and 6 tricalcium phosphate. Compounds which inhibit the transformation of calcium phosphate nuclei to hydroxyapatite and its subsequent crystal growth are known to be effective in restricting calculus deposition in vivo. Such compounds include the diphosphonates, polyphosphates, and zinc. Under physiological conditions, apatites tend to be calcium-deficient with matching HP042- groups. If these groups are displaced, then crystal growth is inhibite

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11

Doroshenko, A. E., V. K. Krut’ko, O. N. Musskaya, S. M. Rabchinsky, and A. I. Kulak. "Electrodeposition of calcium phosphate coatings in polyvinyl alcohol." Physics and Chemistry of Materials Treatment 6 (2022): 17–25. http://dx.doi.org/10.30791/0015-3214-2022-6-17-25.

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Brushite coatings were obtained on titanium by the method of electrochemical deposition from Ca(NO3)2/NH4H2PO4 electrolyte at Ca/P = 1.67, pH = 4 and a constant voltage of 15 V or a current density of 20 mA/cm2 for 20 min. In a medium of 0.01 – 0.10 % polyvinyl alcohol at a constant voltage of 15 V, are deposited single-phase brushite or monetite coatings are deposited. The addition of 0.01 – 0.10 % polyvinyl alcohol into the electrolyte during deposition at a constant current density of 20 mA/cm2 leads to the formation of composite calcium phosphate coatings containing brushite, calcium hydro

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12

Nomura, Shunsuke, Kanji Tsuru, Shigeki Matsuya, Ichiro Takahashi, and Ishikawa Kunio. "Fabrication of Spherical Carbonate Apatite Using Calcium Sulfate as a Precursor by W/O Emulsion Method." Key Engineering Materials 529-530 (November 2012): 78–81. http://dx.doi.org/10.4028/www.scientific.net/kem.529-530.78.

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We fabricated spherical carbonate apatite from spherical calcium sulfate which was prepared by w/o emulsion method. Calcium sulfate hemihydrate slurry was dropped in oil under continuous stirring and was kept at room temperature for 60 min to obtain set spherical calcium sulfate dihydrate (CaSO42H2O) with approximately 1 mm in diameter. The spherical CaSO42H2O was hydrothermally-treated at 120°C for 24 hours in the presence of 0.4 mol.L-1 disodium hydrogen phosphate and sodium hydrogen carbonate aqueous solution. X-ray diffraction patterns assigned to apatite single phase could be detected fro

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13

Hopwood, Jeremy D., Glyn R. Derrick, David R. Brown, et al. "The Identification and Synthesis of Lead Apatite Minerals Formed in Lead Water Pipes." Journal of Chemistry 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/9074062.

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Phosphate is added to drinking water in the UK to minimise the release of lead from lead water pipes. The phosphate encourages the formation of insoluble lead apatites on the walls of the pipe. Hydroxylpyromorphite Pb5(PO4)3OH is the lead apatite that is most often used to model lead levels in tap water; however, its presence has not been confirmed. Our aims were to identify the lead pipe apatite and synthesise it. The synthetic mineral would then be used in future solubility studies to produce better predictions of lead levels in tap water. XRD and FTIR were used to characterise the minerals

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14

Delgado-González, Laura, Bruno Lartiges, Mathieu Gautier, Stéphane Troesch, and Pascal Molle. "Phosphorus retention by granulated apatite: assessing maximum retention capacity, kinetics and retention processes." Water Science and Technology 83, no. 4 (2021): 792–802. http://dx.doi.org/10.2166/wst.2021.010.

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Abstract Natural apatites have previously shown a great capacity for phosphate retention from wastewater. However, its fine particle size distribution may lead to a premature clogging of the filter. Accordingly, a granulated apatite product was developed and manufactured in order to control the particle size distribution of the media. Experiments were conducted on laboratory columns to assess their phosphorus retention capacity, to identify the processes involved in phosphorus retention and to evaluate their kinetic rates. The results showed phosphorus retention capacities of 10.5 and 12.4 g P

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15

Ren, Fu Zeng, Ren Long Xin, Xiang Ge, and Yang Leng. "An Experimental and Computational Study on Zn-Substituted Hydroxyapatite." Advanced Materials Research 47-50 (June 2008): 1379–82. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.1379.

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Nanocrystalline Zn-substituted calcium hydroxyapatite (HA) powder was synthesized by wet chemical method. Detailed characterization was carried out with both experimental techniques and numerical simulation method. X-ray diffraction (XRD) patterns show the calcium phosphate maintains as the apatite phase when the atomic ratio of Zn/(Zn+Ca) is less than 17% Zn in aqueous solutions. The calcium phosphate crystallinility decreases with the Zn concentration increase. The morphological changes with Zn substitution in HA were investigated by TEM. Lattice parameters of the apatitic samples were deter

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16

Dong, Z. L., and T. J. White. "Crystal structure of calcium vanadate-phosphate fluoride." Powder Diffraction 34, S1 (2019): S23—S26. http://dx.doi.org/10.1017/s0885715619000150.

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Apatite-type materials AI4AII6(BO4)6X2 have two unique cations sites AI and AII, which can host large mono-, di- tri- and tetra-valent cations. The average cation radii will affect the twist angle and lattice constants. However, there are few reports on the influence of B site substitutions on the twist angle and lattice parameters. It is believed that the lattice constant variation as a function of B site substitutions may not follow the same twist-angle model as proposed for A site. This work reports our results on the crystal chemistry of synthetic apatite Ca10(VxP1−xO4)6F2 obtained through

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17

Oyane, Ayako, Masaki Uchida, Yousuke Ishihara, and Atsuo Ito. "Ultra-Structural Study of the Laminin-Apatite Composite Layer Formed on Ethylene-Vinyl Alcohol Copolymer by a Biomimetic Process." Key Engineering Materials 284-286 (April 2005): 227–30. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.227.

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Mechanism of formation of a laminin-apatite composite layer on the surface of an ethylene-vinyl alcohol copolymer (EVOH) using a liquid phase coating process was investigated by transmission electron microscopy (TEM). In this coating process, an EVOH substrate is alternately dipped in calcium and phosphate solutions, and then immersed in a laminin-containing calcium phosphate (LCP) solution. From the results obtained by the present study, formation of the laminin-apatite composite layer on EVOH is likely to proceed via the following events. By the alternate dipping process, particulate amorpho

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18

Maslova, L. Yu, V. K. Krut’ko, O. N. Musskaya, T. V. Safronova, and A. I. Kulak. "Formation of biomimetic apatite on calcium phosphate foam ceramics in the concentrated model solution." Perspektivnye Materialy 10 (2022): 23–30. http://dx.doi.org/10.30791/1028-978x-2022-10-23-30.

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By firing polyurethane foam templates (“STR” brand, 12 pores per cm, China) with a porosity of ~ 65 % at 1200 °С, an open-pore calcium phosphate foam ceramics was obtained using a highly concentrated suspension based on synthetic hydroxyapatite, heat-treated at 800 °С, monocalcium phosphate monohydrate and 0.8 % polyvinyl alcohol. The resulting calcium phosphate foam ceramics after modification in the SBF (Simulated Body Fluid) solution concentrated 5 times (SBF×5) consisted of β-tricalcium phosphate, β-calcium pyrophosphate and biomimetic apatite, had a porosity of 53 – 59 % and a static stre

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19

Yamane, Yuya, Takeshi Yabutsuka, Yusuke Takaoka, Chihiro Ishizaki, Shigeomi Takai, and Shunsuke Fujibayashi. "Surface Modification of Carbon Fiber-Polyetheretherketone Composite to Impart Bioactivity by Using Apatite Nuclei." Materials 14, no. 21 (2021): 6691. http://dx.doi.org/10.3390/ma14216691.

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The authors aimed to impart the apatite-forming ability to 50 wt% carbon fiber-polyetheretherketone composite (50C-PEEK), which has more suitable mechanical properties as artificial bone materials than pure PEEK. First, the 50C-PEEK was treated with sulfuric acid in a short time to form pores on the surface. Second, the surface of the 50C-PEEK was treated with oxygen plasma to improve the hydrophilicity. Finally, fine particles of calcium phosphate, which the authors refer to as “apatite nuclei”, were precipitated on the surface of the 50C-PEEK by soaking in an aqueous solution containing mult

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20

Jerdioui, S., H. Bouammalia, E. Mejdoubi, et al. "Physico-chemical characteristics of Ca/P ratio on the composition and structure of oxygenated apatite." Communications in Science and Technology 9, no. 1 (2024): 100–106. http://dx.doi.org/10.21924/cst.9.1.2024.1385.

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Phosphocalcic apatites have osteoconductive and bioactive properties that make them suitable for bone reconstruction. But, they are inactive against pathogenic microorganisms that can infect bone tissue. To overcome this limitation, we synthesized oxygen-doped phosphocalcic apatites that can release molecular oxygen as a bioactive molecule. We investigated how the calcium-to-phosphorus ratio (Ca/P) gave impacts on the chemical and structural composition of the oxygen-doped phosphocalcic apatites. We here used the double decomposition method, which involved mixing calcium nitrate and diammonium

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21

Yokoi, Taishi, Shinji Tomita, Jin Nakamura та ін. "Apatite Formation on α-Tricalcium Phosphate Modified with Bioresponsive Ceramics in Simulated Body Fluid Containing Alkaline Phosphatase". Biomimetics 9, № 8 (2024): 502. http://dx.doi.org/10.3390/biomimetics9080502.

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Bioresponsive ceramics, a new concept in ceramic biomaterials, respond to biological molecules or environments, as exemplified by salts composed of calcium ions and phosphate esters (SCPEs). SCPEs have been shown to form apatite in simulated body fluid (SBF) containing alkaline phosphatase (ALP). Thus, surface modification with SCPEs is expected to improve the apatite-forming ability of a material. In this study, we modified the surface of α-tricalcium phosphate (α-TCP) using methyl, butyl, or dodecyl phosphate to form SCPEs and investigated their apatite formation in SBF and SBF containing AL

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22

Krut'ko, V. K., L. Yu Maslova, O. N. Musskaya, T. V. Safronova, N. L. Budeiko, and A. I. Kulak. "Bioactive calcium phosphate foam ceramics modified by biomimetic apatite." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 58, no. 2 (2022): 158–68. http://dx.doi.org/10.29235/1561-8331-2022-58-2-158-168.

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By combining the method of replication of polyurethane foam matrices at 1200 °C and modification in model SBF (Simulated Body Fluid) solutions of various compositions, open-pore calcium phosphate foam ceramics with a porosity of 53-60 % was obtained. The architecture and morphology of the calcium phosphate foam ceramics surface was formed by using polyurethane foam matrices («Granufoam», «STR») with different porosity and quantity of open pores. Modification of the calcium phosphate foam ceramics in SBF solutions of various compositions leads to a slight decrease in porosity to 3 %, which indi

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23

Zheng, Hua De, Ying Jun Wang, Qiang Ma, Cheng Yun Ning, and Xiao Feng Chen. "Study of Bio-Mineralization of BCP with Compensation of Calcium and Phosphate Ions." Materials Science Forum 610-613 (January 2009): 1391–94. http://dx.doi.org/10.4028/www.scientific.net/msf.610-613.1391.

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In the present study, an Intelligent Multi-parameter Simulated Evaluation in vitro （IMSE system） was used to study the deposition properties of apatite formation on the surface of biphasic calcium phosphate porous ceramic (BCP) from static and dynamic r-SBF. Results showed that apatite formed on the surface of BCP from static and dynamic r-SBF differed between each other. In static r-SBF, ions were transferred by diffusion, which could not compensate the consuming of calcium ions, and mist apatite layer was formed on the surface of samples. But in the dynamic r-SBF, simulated fluid was adjuste

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24

Rattanachan, Sirirat, Piyanan Boonphayak, and Charussri Lorprayoon. "Original article. Development of chitosan/nanosized apatite composites for bone cements." Asian Biomedicine 5, no. 4 (2011): 499–506. http://dx.doi.org/10.5372/1905-7415.0504.065.

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Abstract Background: Calcium phosphate cements (CPC) is a promising materials for bone defect repair. Nanosized apatite or calcium orthophosphate has a better bioactivity than coarser crystals. Chitosan is produced commercially from chitin that is the structural element in the exoskeleton of crustaceans such as crabs and shrimp. The mixing of nanosized apatite and chitosan may provide the consistency cement, improving mechanical properties of the set bone cement. Objective: Develop nanosized apatite powder with chitosan for bone composite cement. Materials and method: Nanosized apatite was syn

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25

Soumia, Belouafa. "Thermal Behavior and Phase Transformations of Biomimetic Oxygenated Apatites." Der Pharma Chemica 14, no. 4 (2022): 9. https://doi.org/10.4172/0975-413X.14.4.17-25.

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High temperature calcination is an essential step for the production of some apatite-based biomaterials. This requires an in-depth study of thermal stability and transformations during heating. The thermal behavior and phase transformations of biomimetic oxygenated apatites, prepared from different calcium salts (CaCO3, Ca(NO3)2, CaCl2) and orthophosphate (H3PO4), are examined, in the present work by chemical analysis, thermo-gravimetric analysis (TGA), Fouriertransform infrared spectroscopy (FTIR) and by X-ray diffraction (XRD). The thermal analysis gives evidence for the dismutation of oxyge

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26

Belouafa, Soumia, Hassan Chaair, and Khalid Digua. "Thermal Behavior and Phase Transformations of Biomimetic Oxygenated Apatites." Der Pharma Chemica 14, no. 4 (2022): 9. https://doi.org/10.5281/zenodo.13354638.

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High temperature calcination is an essential step for the production of some apatite-based biomaterials. This requires an in-depth study of thermal stability and transformations during heating. The thermal behavior and phase transformations of biomimetic oxygenated apatites, prepared from different calcium salts (CaCO3, Ca(NO3)2, CaCl2) and orthophosphate (H3PO4), are examined, in the present work by chemical analysis, thermo-gravimetric analysis (TGA), Fouriertransform infrared spectroscopy (FTIR) and by X-ray diffraction (XRD). The thermal analysis gives evidence for the dismutation of oxyge

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27

Karamian, Ebrahim, Amirsalar Khandan, Mustafa Eslami, Hassan Gheisari, and Niosha Rafiaei. "Investigation of HA Nanocrystallite Size Crystallographic Characterizations in NHA, BHA and HA Pure Powders and their Influence on Biodegradation of HA." Advanced Materials Research 829 (November 2013): 314–18. http://dx.doi.org/10.4028/www.scientific.net/amr.829.314.

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The mineral or inorganic component of bone is a calcium phosphate idealized as a calcium hydroxyapatite, HA, Ca10(PO4)6(OH)2. Changes in the composition of the apatite affect its lattice parameters, morphology, crystallinity (reflecting crystal size and/or perfection) and finally dissolution properties. In regard to the above points, lattice parameters are expected to have better dissolution properties. Estimation of HA nanocrystallite size lattice parameters is one of the most important factors for dissolution properties of bone apatites. In present work, the composition of apatite induce com

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Feng, Bo, Jie Weng, Shao Xing Qu, and Xing Dong Zhang. "Fabrication of Microporous Apatite Coating on Titanium by a Novel Chemical Method." Key Engineering Materials 284-286 (April 2005): 231–34. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.231.

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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.

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He, Yuan, Ling Feng Dai, Shi Hui Wang, Ya Nan Sun, Wei Shi, and Dong Tao Ge. "Towards Enhanced Bioactivity: Calcium Ion-Doped Polypyrrole." Advanced Materials Research 941-944 (June 2014): 1168–73. http://dx.doi.org/10.4028/www.scientific.net/amr.941-944.1168.

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Based on the unique redox property of electrically conductive polymers, Ca2+ was incorporated into polypyrrole (PPy) film that previously doped with polyelectrolyte heparin. Then the apatite-forming ability of the Ca2+-doped PPy was examined by a biomimetic method using stimulated body fluid (SBF), which has ion concentration nearly equal to those of human blood plasma. It was found that the Ca2+-doped PPy successfully formed bonelike apatite deposition on its surface after soaking in SBF for only 3 days, whereas the similar apatite deposition was formed on Ca2+-free PPy after soaking in SBF f

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Molle, P., A. Liénard, A. Grasmick, A. Iwema, and A. Kabbabi. "Apatite as an interesting seed to remove phosphorus from wastewater in constructed wetlands." Water Science and Technology 51, no. 9 (2005): 193–203. http://dx.doi.org/10.2166/wst.2005.0318.

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Intensive use of phosphates has resulted in high P levels in surface waters and therefore eutrophication problems. Over the last decade many studies have revealed the advantage of using specific materials with efficient phosphorus retention capacities. Recent studies state that Ca materials are of particular interest for long-term retention of P, but can induce negative effects. To improve P retention and avoid negative counter-effects we tested the potential of natural apatites. Apatite sorption was evaluated using batch and open reactor experiments. Batch experiments identify sorption mechan

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31

LeGeros, Racquel Z., Dindo Q. Mijares, Fang Yao, et al. "Consequences of Fluoride Incorporation on Properties of Apatites." Key Engineering Materials 309-311 (May 2006): 697–700. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.697.

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Fluoride, when incorporated in the apatite, stabilizes the structure. The purpose of this study was to determine the consequences of fluoride (F) substitution on the physico-chemical properties of apatites. F-containing apatites were prepared by precipitation or by hydrolysis of CaHPO4 in solutions containing different F concentrations and characterized using x-ray diffraction, FT-IR spectroscopy, scanning electron microscopy, thermogravimetry and chemical analyses. Results showed that F incorporation have the following effects: (a) decrease in a-axis dimension, (b) increase in crystal size an

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32

Chaikina, Marina V., Natalia V. Bulina, Olga B. Vinokurova, et al. "Possibilities of Mechanochemical Synthesis of Apatites with Different Ca/P Ratios." Ceramics 5, no. 3 (2022): 404–24. http://dx.doi.org/10.3390/ceramics5030031.

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Apatite is widely used in medicine as a biomaterial for bone tissue restoration. Properties of apatite depend on its composition, including the Ca/P ratio. This paper shows what range of Ca/P ratio can be attained in apatite by the mechanochemical method of synthesis, providing fast formation of a single-phase product. The synthesis was carried out from a reaction mixture of CaHPO4 and CaO at different Ca/P ratios in the range of 1.17–2.10. The products were studied by PXRD, FTIR and NMR spectroscopy, HRTEM, and STA. In mixtures with a low initial Ca/P ratio (1.17–1.48), directly in the mill,

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33

Honda, Daiki, Akari Takeuchi, and Ishikawa Kunio. "Basic Properties of Starfish Derived Calcium Carbonate and its Phase Transformation to Carbonate Apatite." Key Engineering Materials 529-530 (November 2012): 40–43. http://dx.doi.org/10.4028/www.scientific.net/kem.529-530.40.

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Feasibility of starfish bone to be a source material for apatite bone substitute was investigated in the present study because starfish bone is known to be porous calcium carbonate. Starfish bone was assembly of Mg containing calcite granules. And the calcite granules had fully interconnected porous structure with approximately 20 µm of pore size. After the hydrothermal treatment of the calcite granules in Na2HPO4 aqueous solution, the granules were gradually transformed to apatite. Therefore, starfish derived calcium carbonate would be a candidate of a source material for carbonate apatite bo

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Amador, G., H. Gautier, V. Le Mabecque, et al. "In Vivo Assessment of the Antimicrobial Activity of a Calcium-Deficient Apatite Vancomycin Drug Delivery System in a Methicillin-Resistant Staphylococcus aureus Rabbit Osteomyelitis Experimental Model." Antimicrobial Agents and Chemotherapy 54, no. 2 (2009): 950–52. http://dx.doi.org/10.1128/aac.00434-09.

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ABSTRACT The antimicrobial activities of calcium-deficient apatite loaded with different concentrations (25, 100, and 500 μg/mg) of vancomycin as a filling biomaterial were evaluated in a methicillin-resistant Staphylococcus aureus (MRSA) rabbit acute osteomyelitis model. Bacterial counts in bone, bone marrow, and joint fluid samples treated with forms of the apatite were compared to those in tissue samples receiving a constant intravenous vancomycin infusion after 4 days. This study demonstrates that using a calcium-deficient apatite loaded with vancomycin dramatically decreases the bacterial

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He, Li Ping, Zong Zhang Chen, and Yiu Wing Mai. "Induction Ability of CAA and Anti-Corrosion Property of Inductively Formed Apatite/Al₂O₃." Advanced Materials Research 41-42 (April 2008): 75–80. http://dx.doi.org/10.4028/www.scientific.net/amr.41-42.75.

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Ca-containing anodic alumina (CAA) has been successfully prepared by anodizing Al film in an alkali solution at a constant voltage and subsequently electro-depositing calcium salts on and into porous anodic alumina. This paper studied the induction ability of Ca-containing anodic alumina (CAA) for calcium phosphates salts by immersing CAA in a simulated body fluid (SBF). The morphologies and compositions of the inductive coating are studied in depth using SEM and XRD. The results show that the porous Ca-containing anodic alumina (CAA) exhibits good induction ability of calcium phosphates in SB

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Kalinkina, E. V., A. M. Kalinkin, A. G. Ivanova, E. A. Kruglyak, and B. I. Gurevich. "Composite mechanically activated binders based on power plant fly ash, calcite and two-water gypsum." Transactions of the Kоla Science Centre. Series: Natural Sciences and Humanities 1, no. 2/2022 (2022): 50–57. http://dx.doi.org/10.37614/2949-1185.2022.1.2.006.

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The paper presents the results of studying the binding properties of a mechanically activated composition including fly ash from the Apatity Thermal Power Plant with increased calcium content, calcite concentrate produced from apatite-carbonatite ores of the Kovdorsky deposit and natural gypsum stone. It was found that the composition, depending on the mixing ratio and curing conditions, displays characteristics of both hydraulic binder similar to lime-ash one and air binder similar to gypsum.

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Smith, D. F., and D. M. Reid. "Hydroxyapatite Associated Disease in an Elderly Female: Differentiation from Aseptic Necrosis." Scottish Medical Journal 34, no. 2 (1989): 438–39. http://dx.doi.org/10.1177/003693308903400208.

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The crystal arthropathies caused by monosodium urate and calcium pyrophosphate dihydrate are commonly recognised, but the destructive arthropathy associated with the deposition of calcium hydroxy-apatite is less well known in general clinical practice.1 We describe a case with many of the classical features of hydroxy-apatite associated disease and discuss the features differentiating the condition from aseptic necrosis.

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Asimeng, B. O., E. K. Tiburu, K. Kan-Dapaah, J. K. Efavi, R. Asiamah, and D. W. Afeke. "Influence of preferred orientation on the bioactivity of hydroxyapatite: a potential tooth repair and implant surface coating material." Cerâmica 66, no. 379 (2020): 340–46. http://dx.doi.org/10.1590/0366-69132020663792881.

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Abstract Bioactive hydroxyapatite (HAp) material was synthesized using a simple wet chemical precipitation and heat-treatment method from snail (Achatina achatina) shells and a phosphate-containing solution. According to X-ray diffraction patterns obtained, the heat-treatment caused a crystallographic preferred orientation along the HAp c-axis and thus, affected the material mineralization and bioactivity modeled in vitro using simulated body fluid (SBF) for 7 and 21 days. After 21 days of immersion, calcium and phosphate mineral concentrations in SBF decreased by 66% and 83%, respectively. Th

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Osaka, A., Y. Miura, K. Takeuchi, M. Asada, and K. Takahashi. "Calcium apatite prepared from calcium hydroxide and orthophosphoric acid." Journal of Materials Science: Materials in Medicine 2, no. 1 (1991): 51–55. http://dx.doi.org/10.1007/bf00701687.

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Santhakumar, Syama, Ayako Oyane, Maki Nakamura, Yuto Yoshino, Mohammed Katib Alruwaili, and Hirofumi Miyaji. "Bone Tissue Regeneration by Collagen Scaffolds with Different Calcium Phosphate Coatings: Amorphous Calcium Phosphate and Low-Crystalline Apatite." Materials 14, no. 19 (2021): 5860. http://dx.doi.org/10.3390/ma14195860.

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Surface-mineralized collagen sponges have attracted much attention as scaffolds for bone tissue engineering. Recently, we developed amorphous calcium phosphate (ACP) and low-crystalline apatite coating processes on collagen sponges. In the present study, we applied these coating processes to granular collagen sponges (referred to as Col) to compare the bone tissue regeneration capabilities of ACP-coated and apatite-coated Col (referred to as Col-ACP and Col-Ap, respectively) using a rat cranial bone defect model. According to micro-CT and histological analyses, Col-Ap enhanced bone tissue rege

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You, Caihong, Toshiki Miyazaki, Eiichi Ishida, Masahiro Ashizuka, and Chikara Ohtsuki. "Bioactive Organic-Inorganic Hybrids Prepared from Poly(Vinyl Alcohol) via Modification with Metal Oxides and Calcium Salt." Key Engineering Materials 309-311 (May 2006): 1153–56. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.1153.

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Organic polymers with ability of apatite formation in body environment are expected as novel bone substitutes having not only bone-bonding ability, i.e. bioactivity, but also mechanical performance analogous to natural bone. Several metal oxides have been found to be effective for the apatite deposition in body environment. In addition, release of calcium ions from the materials significantly enhances it. In this study, we attempted to synthesize bioactive organic-inorganic hybrids from poly(vinyl alcohol) (PVA) by incorporation of titanium oxide or zirconium oxide as well as calcium salt. Abi

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Whang, Chin Myung, Do Won Seo, and Y. H. Kim. "Mechanism of Apatite Formation on Sol-Gel Derived PDMS-Modified SiO₂-CaO-P₂O₅ Hybrids with Various P₂O₅ Content." Key Engineering Materials 280-283 (February 2007): 1589–94. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.1589.

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The mechanism of apatite formation on the surface of novel PDMS modified SiO2-CaO- P2O5 hybrids is presented. The bioactive hybrids with different P2O5 content were synthesized by sol-gel method and soaked in the simulated body fluid (SBF) for different periods. The surface and the cross-section of the specimens were examined by use of Fourier transform infrared reflection spectroscopy, thin-film X-ray diffraction technique and scanning electron microscopy. The PDMS-SiO2-CaO-P2O5 hybrid containing 0.03 mole ratio of TEP(triethyl phosphate) / TEOS (tetraethoxysilane) exhibited faster apatite fo

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Wang, Xiu Peng, Atsuo Ito, Xia Li, Yu Sogo, and Ayako Oyane. "FGF-2-Zinc-Apatite Composite Layers on External Fixation Rod for Promoting Cell Activity." Key Engineering Materials 529-530 (November 2012): 480–85. http://dx.doi.org/10.4028/www.scientific.net/kem.529-530.480.

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FGF-2-apatite and FGF-2-zinc-apatite composite layers were formed on commercially available anodically oxidized Ti external fixation rods using FGF-2-and ZnCl2-containing supersaturated calcium phosphate solutions. The FGF-2-zinc-apatite composite layers precipitated on the Ti external fixation rods significantly enhanced proliferation of fibroblastic NIH3T3 and osteoblastic MC3T3-E1 cells in vitro.

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LeGeros, John P., Shu Jie Lin, Dindo Q. Mijares, Fred Dimaano, and Racquel Z. LeGeros. "Electrochemically Deposited Calcium Phosphate Coating on Titanium Alloy Substrates." Key Engineering Materials 284-286 (April 2005): 247–50. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.247.

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Plasma-sprayed HA coating combines the strength of the metal and the bioactivity of the HA. However, this method has several disadvantages. Alternatives to the plasma-spray method such as electrochemical deposition (ECD) and biomimetic or precipitation methods are being explored. The purpose of this study was to develop an ECD method for coating Ti alloy substrate with different calcium phosphates (octacalcium phosphate, calcium deficient apatite, carbonatesubstituted apatite, fluoride-substituted apatite). Pairs of Ti6Al4V plates that have been mechanically polished, ultrasonically cleaned, a

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Maeda, Hirotaka, Toshihiro Kasuga, Masayuki Nogami, et al. "Biomimetic apatite formation on poly(lactic acid) composites containing calcium carbonates." Journal of Materials Research 17, no. 4 (2002): 727–30. http://dx.doi.org/10.1557/jmr.2002.0104.

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Poly(lactic acid) composites containing a mixture of calcium carbonates (vaterite, aragonite, and calcite) were prepared by a carbonation process in methanol. Soaking of the composites for 3 h in simulated body fluid (SBF) at 37 °C resulted in the deposition of bonelike apatite particles on the composite surface. After soaking the composites, vaterite phase in the composites was forward to dissolve rapidly, resulting in increase the supersaturation of the apatite in SBF. 13C cross-polarization magic angle spinning nuclear magnetic resonance (13C CP/MAS-NMR) spectra of the composites suggested

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Faris, Adam, Hakan Engqvist, Jesper Lööf, Mikael Ottosson, and Leif Hermansson. "In Vitro Bioactivity of Injectable Ceramic Orthopaedic Cements." Key Engineering Materials 309-311 (May 2006): 833–36. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.833.

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The objective of this paper is to investigate and compare the in vitro bioactivity of three injectable cements for orthopaedic applications. The cements were all based on chemically bonded ceramics technology; calcium phosphate (Norian SRS), and experimental versions of calcium silicate and calcium aluminate cements. The cements were mixed with their respective liquids and were after setting stored in phosphate buffered saline at 37 °C for time periods of 1h, 24 h, 7 days and 30 days. After storage the samples were analysed with scanning electron microscopy (SEM), thin film X-Ray diffraction (

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Ota, Toshitaka, Takahiro Eitsuka, Haruki Yoshida, and Nobuyasu Adachi. "Porous Apatite Ceramics Derived from Woods." Advanced Materials Research 11-12 (February 2006): 247–50. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.247.

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Porous calcium phosphate ceramics (apatite and TCP) with wood-like microstructures, analogous to that of silicified wood, were prepared from natural woods as templates. The production of these ceramic woods was performed by the following process: (1) infiltration with an ethanol solution containing tri-ethyl phosphate and calcium nitrate tetra-hydrate into wood specimens, (2) drying to form a calcium phosphate gel in the cell structure, (3) firing in air to form apatite and TCP. The microstructure of the obtained ceramic woods retained the same structure as that of the raw woods: with the pore

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JOKSA, Aiga Anna, and Karlis Agris GROSS. "Nature-inspired Apatite Production: Steam Processing of Calcium Carbonate and Tricalcium Phosphate Nanosized Powder Blends." Materials Science 29, no. 3 (2023): 323–31. http://dx.doi.org/10.5755/j02.ms.32132.

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Green production of materials is crucial to protect the environment. In this article, a low-temperature steam synthesis strategy for apatite production is shown for limiting chemical pollution and enabling the control of crystallinity. Steam processing produced apatite from calcium carbonate and tricalcium phosphate nanosized powders. Interdiffusion between amorphous precursors gave hydroxyapatite accompanied by calcium-deficient hydroxyapatite. This study unfolds the potential of hydrothermal processing in steam as a synthesis strategy that has been forgotten since the 1950s showing where two

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You, Caihong, Toshiki Miyazaki, Eiichi Ishida, Masahiro Ashizuka, Chikara Ohtsuki, and Masao Tanihara. "Apatite Deposition on Organic-Inorganic Hybrids Synthesized from Poly(Vinyl Alcohol) and Various Metal Oxides." Key Engineering Materials 284-286 (April 2005): 469–72. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.469.

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Organic polymers with ability of apatite formation in body environment are expected as novel bone substitutes having not only bone-bonding ability, i.e. bioactivity, but also mechanical performance analogous to natural bone. Several metal oxides have been found to be effective for the apatite deposition in body environment. In addition, release of calcium ions from the materials significantly enhances it. In this study, we attempted to synthesize bioactive organic-inorganic hybrids from Poly(vinyl alcohol) (PVA) by incorporation of various metal oxides and calcium salt. Silica and molybdenum o

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Yamaguchi, Seiji, Phuc Thi Minh Le, Morihiro Ito, Seine A. Shintani, and Hiroaki Takadama. "Tri-Functional Calcium-Deficient Calcium Titanate Coating on Titanium Metal by Chemical and Heat Treatment." Coatings 9, no. 9 (2019): 561. http://dx.doi.org/10.3390/coatings9090561.

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The main problem of orthopedic and dental titanium (Ti) implants has been poor bone-bonding to the metal. Various coatings to improve the bone-bonding, including the hydroxyapatite and titania, have been developed, and some of them have been to successfully applied clinical use. On the other hand, there are still challenges to provide antibacterial activity and promotion of bone growth on Ti. It was shown that a calcium-deficient calcium titanate coating on Ti and its alloys exhibits high bone-bonding owing to its apatite formation. In this study, Sr and Ag ions, known for their promotion of b

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