Journal articles: 'Phosphate de calcium'

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Numata, Yasuko, Toshiro Sakae, Taketoshi Suwa, Hiroshi Nakada, Racquel Z. LeGeros, and Kihei Kobayashi. "Qualitative and Quantitative Evaluation of Bone and Synthetic Calcium Phosphates Using Raman Spectroscopy." Key Engineering Materials 361-363 (November 2007): 135–38. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.135.

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The purpose of this study was to evaluate synthetic calcium phosphates and animal bones using Raman spectroscopy and explore the possibility of its application in characterizing newly formed bone around implants. Synthetic calcium phosphates (monobasic calcium phosphate, dibasic calcium phosphate, tribasic calcium phosphate, fiber apatite, hydroxyapatite and carbonate hydroxyapatite) and animal bones (from pig, cow, rabbit with and without implants) were analyzed in this study. Slight differences in the Raman bands among the 7 types of synthetic calcium phosphate were observed. Furthermore, a 3 cm-1 difference was noted in the bands of the main PO4 3- in rabbit’s bone formed around the implant, compared to the existing bone, suggesting a difference in the molecular structure between the existing and newly formed bones.

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Enax, Joachim, Frederic Meyer, Erik Schulze zur Wiesche, and Matthias Epple. "On the Application of Calcium Phosphate Micro- and Nanoparticles as Food Additive." Nanomaterials 12, no. 22 (November 19, 2022): 4075. http://dx.doi.org/10.3390/nano12224075.

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The human body needs calcium and phosphate as essential nutrients to grow bones and teeth, but they are also necessary for many other biochemical purposes (e.g., the biosynthesis of phospholipids, adenosine triphosphate, ATP, or DNA). The use of solid calcium phosphate in particle form as a food additive is reviewed and discussed in terms of bioavailability and its safety after ingestion. The fact that all calcium phosphates, such as hydroxyapatite and tricalcium phosphate, are soluble in the acidic environment of the stomach, regardless of the particle size or phase, means that they are present as dissolved ions after passing through the stomach. These dissolved ions cannot be distinguished from a mixture of calcium and phosphate ions that were ingested separately, e.g., from cheese or milk together with soft drinks or meat. Milk, including human breast milk, is a natural source of calcium and phosphate in which calcium phosphate is present as nanoscopic clusters (nanoparticles) inside casein (protein) micelles. It is concluded that calcium phosphates are generally safe as food additives, also in baby formula.

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Trautvetter, Ulrike, Bianka Ditscheid, Gerhard Jahreis, and Michael Glei. "Calcium and Phosphate Metabolism, Blood Lipids and Intestinal Sterols in Human Intervention Studies Using Different Sources of Phosphate as Supplements—Pooled Results and Literature Search." Nutrients 10, no. 7 (July 20, 2018): 936. http://dx.doi.org/10.3390/nu10070936.

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Phosphates are associated with negative physiological effects. The objectives of this publication were to compare differential effects of supplementation with calcium phosphate or phosphate alone in healthy humans. Four adult human studies were conducted with pentacalcium hydroxy-trisphosphate supplementation (CaP; 90 subjects) and their data were pooled for assessment. For literature search; PubMed and ISI Web of Knowledge were used and 21 items were assigned to three main topics. The pooled study results show that following CaP supplementation, faecal calcium and phosphorus and urinary calcium were increased, blood lipids were positively modulated, and faecal bile acids were increased, as compared with placebo. The literature search reveals that following calcium phosphate supplementation, urinary calcium was increased. Following solely phosphate supplementation, urinary phosphorus was increased and urinary calcium was decreased. Postprandial calcium concentrations were increased following calcium phosphate supplementation. Postprandial phosphate concentrations were increased following solely phosphate supplementation. Calcium phosphate supplementation resulted in rather positively modulated blood lipids and gut-related parameters. The presented results show the relevance to distinguish between calcium phosphate and solely phosphate supplementations, and the importance of a balanced calcium and phosphorus intake.

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Cats, A., N. H. Mulder, E. G. E. de Vries, E. T. H. G. J. Oremus, W. M. T. Kreumer, and J. H. Kleibeuker. "Calcium phosphate." European Journal of Cancer Prevention 2, no. 5 (September 1993): 409–16. http://dx.doi.org/10.1097/00008469-199309000-00008.

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Labgairi, K., A. Borji, M. Kaddami, and A. Jourani. "Kinetic Study of Calcium Phosphate Precipitation in the System H3PO4-Ca(OH)2-H2O at 30°C." International Journal of Chemical Engineering 2020 (November 10, 2020): 1–9. http://dx.doi.org/10.1155/2020/2893298.

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The precipitation kinetics of calcium phosphates, namely, hydroxyapatite (HAP), dicalcium phosphate dihydrate (DCPD), dicalcium phosphate anhydrous (DCPA), and monocalcium phosphate monohydrate (MCPM), were studied at 30°C by mixing calcium hydroxide, water, and phosphoric acid. The studied mixture was selected according to the stability domain of different calcium phosphates by referring to the phase diagram of the ternary system of H3PO4-Ca(OH)2-H2O at 30°C. The precipitation reaction has been monitored by following the changes in the conductivity, pH, and calcium concentration. The solid phases formed at different stages of this precipitation were characterized by X-ray diffraction.

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Holt, Carl, Mathea J. J. M. van Kemenade, Lowell S. Nelson, Lindsay Sawyer, John E. Harries, Raymond T. Bailey, and David W. L. Hukins. "Composition and structure of micellar calcium phosphate." Journal of Dairy Research 56, no. 3 (May 1989): 411–16. http://dx.doi.org/10.1017/s0022029900028880.

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SummaryMicellar calcium phosphate has the chemical composition and physicochemical properties that are consistent with it being a complex of the phosphate centres of casein with an acidic amorphous calcium phosphate. Similar acidic amorphous calcium phosphates have been prepared in the laboratory and for these, as well as for micellar calcium phosphate, the most appropriate crystalline model compound from which the short-range structure may be derived is brushite, CaHPO4.2H2O. The predicted secondary structures around sites of phosphorylation in the Ca2+-sensitive caseins often comprise an α-hclix-loop-α-helix motif with the sites of phosphorylation in the loop region. This motif may be important in linking the colloidal calcium phosphate with casein in native casein micelles.

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Glazov, I. E., V. K. Krut’ko, R. A. Vlasov, O. N. Musskaya, and A. I. Kulak. "Nanocomposites based on apatitic tricalcium phosphate and autofibrin." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 57, no. 4 (December 3, 2021): 413–23. http://dx.doi.org/10.29235/1561-8331-2021-57-4-413-423.

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Nanocomposites based on apatitic tricalcium phosphate in an autofibrin matrix were obtained by precipitation at a Ca/P ratio of 1.50, pH 9 and a maturation time from 30 min to 7–14 days. The resorbability of nanocomposites was determined by the composition of calcium phosphates, which, during long-term maturation, formed as the calcium-deficient hydroxyapatite with a Ca/P ratio of 1.66, whereas biopolymer matrix favored the formation of more soluble calcium phosphates with a Ca/P ratio of 1.53–1.59. It was found that the fibrin clot stabilized, along with apatitic tricalcium phosphate, the phase of amorphous calcium phosphate, which after 800 °C was transformed into resorbable α-tricalcium phosphate. Citrated plasma inhibited the conversion of apatitic tricalcium phosphate into stoichiometric hydroxyapatite, which also facilitated the formation of resorbable β-tricalcium phosphate after 800 °C. The combined effect of the maturation time and the biopolymer matrix determined the composition, physicochemical and morphological properties of nanocomposites and the possibililty to control its extent of resorption

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Tariq, U., Z. Haider, K. Chaudhary, R. Hussain, and J. Ali. "Calcium to phosphate ratio measurements in calcium phosphates using LIBS." Journal of Physics: Conference Series 1027 (May 2018): 012015. http://dx.doi.org/10.1088/1742-6596/1027/1/012015.

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Conti, Claudia, Léa Cutard, Alessandra Botteon, Luigi Brambilla, Nicoletta Marinoni, Marco Realini, Maria Catrambone, Elena Possenti, and Chiara Colombo. "Investigation of Calcium and Magnesium Phosphate Crystals in Stones Treated with Diammonium Hydrogen Phosphate Conservation Product: Potential of Micro-Raman Spectroscopy." Crystals 13, no. 8 (August 5, 2023): 1212. http://dx.doi.org/10.3390/cryst13081212.

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This study is aimed at investigating crystals (calcium and magnesium phosphates) formed due the interaction of an inorganic conservation treatment (diammonium hydrogen phosphate—DAP) with carbonatic (calcitic and dolomitic) stones through micro-Raman Spectroscopy. The addressed questions concern (i) the identification of magnesium and calcium phosphate minerals crystallized within dolomitic stone samples with a different degree of conservation state and treated with two different DAP solution molarities and (ii) the distinction of complex calcium phosphate mixtures (hydroxyapatite—HAP and octa calcium phosphate—OCP) crystallized within a calcarenite stone treated with DAP. A statistically relevant number of Raman spectra have been acquired in sample cross sections and curve fitting analysis has been performed for the in-depth interpretation of data. The outcomes indicate that Raman Spectroscopy is an effective alternative method for the identification of poorly crystalline calcium phosphates (not easily detectable with X-ray diffraction), even when scarcely present in mixture with magnesium phosphates. Evidence of the Raman analytical capability and high potential to distinguish HAP and OCP in calcitic stones are also presented and discussed.

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Farrell, Harold M., Beverly E. Maleeff, and Cecilia T. Leung. "Ultrastructural localization of alkaline phosphatase in lactating rat mammary gland." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 390–91. http://dx.doi.org/10.1017/s0424820100104017.

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Alkaline phosphatase is found in almost all nucleated mammalian cells as well as in many microorganisms. In animal tissues, it is often found associated with plasma membranes and also has been indirectly implicated in the accumulation of calcium-phosphate in calcifying tissue, osteoblasts and odontoblasts. In the secretion of milk, vesicles accumulate casein and colloidal calcium-phosphate, while in a separate pathway milk fat is secreted and bounded by the apical plasma membrane. Alkaline phosphatase is found in milk, and all milks contain both colloidal calcium-phosphate and fat globule membranes which are derived in part from the plasma membrane. Previous studies had suggested that mammary alkaline phosphatase is limited to nonsecretory myoepithelial cells, but recent work has indicated that intracellular alkaline phosphatase is cryptic. We therefore decided to investigate the cytochemical distribution of alkaline phosphatase in mammary secretory cells, and to determine if it could participate in calcium-phosphate accumulation in milk.

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11

Kazakova, G. K., T. V. Safronova, and T. B. Shatalova. "Ceramics based on powders synthesized from ammonium hydrophosphate and acetates of calcium and magnesium." Materials Science, no. 4 (April 20, 2021): 33–40. http://dx.doi.org/10.31044/1684-579x-2021-0-04-33-40.

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Ceramics the phase composition of which included tricalcium phosphate, calcium magnesium ortophosphate and magnesium pyrophosphate has been produced from nanosized powders synthesized by chemical deposition from 1M aqueous solutions of ammonium hydrogen phosphate and calcium and / or magnesium acetates. According to XRD analysis the phase composition of the powder synthesized from calcium acetate included calcium hydroxyapatite Ca5(PO4)3(OH), octacalcium phosphate Ca8H2(PO4)6·5H2O and brushite CaHPO4·2H2O. The phase composition of the powder synthesized from magnesium acetate included struvite MgNH4PO4·6H2O. And the phase composition of the powder synthesized from solution containing calcium and magnesium acetates at the cation ratio Са: Mg = 9: 1 included hydroxyapatite Ca5(PO4)3(OH), whitlockite Ca18Mg2H2(PO4)14, and struvite MgNH4PO4·6H2O. Ceramic materials containing the bioresorbable and biocompatible phases of calcium and / or magnesium phosphates can be used to make bone implants for treatment of bone tissue defects. Keywords: tricalcium phosphate, calcium magnesium orthophosphate, magnesium pyrophosphate, whitlockite, octacalcium phosphate, hydroxyapatite, brushite, struvite, ceramics.

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Tamai, Masato, Ryusuke Nakaoka, and Toshie Tsuchiya. "Cytotoxicity of Various Calcium Phosphate Ceramics." Key Engineering Materials 309-311 (May 2006): 263–66. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.263.

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The cytotoxicity of five calcium phosphate ceramics, hydroxyapatite (HAp), flouroapatite (FAp), α-tricalcium phosphate (α-TCP), β-tricalcium phosphate (β-TCP) and tetracalcium phosphate (TTCP), was investigated. Based on the guidelines of biological test for medical devices in Japan, a cytotoxicity test of these calcium phosphates was carried out using Chinese hamster V79 lung fibroblasts. The cytotoxic study revealed that FAp and α-TCP showed high cytotoxicities. From various analyses, it was considered that the cytotoxicity of the FAp was due to fluorine ions extracted in a culture medium and the cytotoxicity of α-TCP resulted from a decrease in pH of the medium by the phosphoric acid, which produced by hydrolysis of( the α-TCP.

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13

Hegde, AM, N. Naik, and S. Kumari. "Comparison of Salivary Calcium, Phosphate and Alkaline Phosphatase Levels in Children with Early Childhood Caries after Administration of Milk, Cheese and GC Tooth Mousse: An in Vivo Study." Journal of Clinical Pediatric Dentistry 38, no. 4 (July 1, 2014): 318–25. http://dx.doi.org/10.17796/jcpd.38.4.l172u301208153v2.

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Background and Objectives: This study compares the Salivary Calcium, Phosphate and Alkaline Phosphataselevels in children with Early Childhood Caries after administration of Milk, Cheese and GC Tooth Mousse to a control group of caries resistant children. Study design: 90 kindergarten children both males and females aged 5 years, from the South Canara region were included in the study. Based on the dmfs score, children were divided into 3 groups: Control group, ECC group and S-ECC group. The Salivary Calcium, Phosphate and Alkaline Phosphatase levels in the sample were assessed before and after administration of Milk, Cheese and GC Tooth Mousse at three different intervals, i.e within 5 minutes, 30 minutes and 60 minutes by using Spectrophotometry. Results: The mean Salivary Calcium levels were higher in caries free group whereas Phosphate and Alkaline Phosphatase were lower in the caries free group which was statistically highly significant (p<0.001). The Tooth Mousse group showed higher bioavailability of calcium and phosphate which was statistically highly significant (p<0.001). Salivary Calcium and Phosphate levels within 5 minutes after application of Milk, Cheese and Tooth Mousse were higher than at 30 and 60 minutes. Salivary Alkaline Phosphatase levels were lower than the baseline values at all the 3 intervals after administration of Milk, Cheese and Tooth Mousse and was statistically not significant (p≯0.05). Conclusion: Saliva should be saturated with Calcium and Phosphate to affect their bioavailability in amounts adequate for remineralizaton. Milk, Cheese and GC Tooth Mousse applicaton were equally beneficial in saturating the saliva with adequate amount of Calcium and Phosphate.

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Nancollas, George H., and Zachary J. Henneman. "Calcium oxalate: calcium phosphate transformations." Urological Research 38, no. 4 (July 13, 2010): 277–80. http://dx.doi.org/10.1007/s00240-010-0292-3.

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15

Mardziah, C. M., Mohamad Firdaus Abdul Wahid, Koay Mei Hyie, Nik Rozlin Nik Masdek, and Z. Salleh. "Effect of Sintering Temperature on Zinc Substituted Calcium Phosphate Ceramics." Materials Science Forum 890 (March 2017): 209–12. http://dx.doi.org/10.4028/www.scientific.net/msf.890.209.

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Calcium phosphate ceramics were substituted with several concentrations of zinc ions (0, 5, 10 and 15 mol%) using precipitation method. The effect of sintering temperature at 900 and 1000°C on zinc substituted calcium phosphate ceramics were observed. By increasing the sintering temperature, XRD peaks for zinc substituted calcium phosphate ceramics changed significantly. At sintering temperature of 900°C, hydroxyapatite phase was the major phase in the calcium phosphates containing 0 and 5 mol% zinc. However, at the sintering temperature of 1000°C, hydroxyapatite phase was partly transformed to another phase which was tricalcium phosphate. FESEM observations at sintering temperature of 1000°C exhibit that the particle size of the samples increased with addition of more zinc ions.

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Franczak, Priscila Ferraz, Nelson Heriberto Almeida Camargo, Pricyla Corrêa, and Enori Gemelli. "Synthesis and Characterization of Hydrated Calcium Phosphate: Precursors for Obtaining Biocements." Materials Science Forum 798-799 (June 2014): 443–48. http://dx.doi.org/10.4028/www.scientific.net/msf.798-799.443.

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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.

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Possamai, Maicon Douglas, Nelson Heriberto Almeida Camargo, Daiara Floriano-Silva, Marli Baltazar Roesler Eckstein, and Priscila Ferraz Franczak. "Synthesis and Characterization of a Nanostructured Matrix of Hydrated Calcium Phosphate." Materials Science Forum 881 (November 2016): 159–64. http://dx.doi.org/10.4028/www.scientific.net/msf.881.159.

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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.

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WENG, WENJIAN, YANBO GAO, LILI PAN, YANBAO LI, PIYI DU, GE SHEN, and GAORONG HAN. "PREPARATION AND MORPHOLOGY OF POROUS NANOCALCIUM PHOSPHATE/POLY(L-LACTIC ACID) COMPOSITES." International Journal of Nanoscience 04, no. 04 (August 2005): 517–23. http://dx.doi.org/10.1142/s0219581x05003553.

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Biodegradable porous materials can serve as a scaffold in tissue engineering. In this work, highly porous nano-calcium phosphate (NCP)/poly(L-lactic acid)(PLLA) composites were prepared by a thermally induced phase separation technique. Five calcium phosphates with different biodegradation rate were selected, i.e. amorphous calcium phosphate, α-tricalcium phosphate, β-tricalcium phosphate and biphasic α/β-tricalcium phosphate. The results showed that the NCP particles could be homogenously incorporated into pore walls; the composites had a porosity of ~90%, and a pore size of ~200 μm. From the point of view of materials science, the obtained porous NCP/PLLA composites demonstrate to have a capability of applying in bone tissue engineering.

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Öhman, Sten, Lasse Larsson, and Hans-Göran Tiselius. "Clinical Significance of Phosphate in Calcium Oxalate Renal Stones." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 29, no. 1 (January 1992): 59–63. http://dx.doi.org/10.1177/000456329202900108.

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We analysed calcium, magnesium, oxalate, citrate, urate and creatinine in urine and calculated risk factors in patients who had formed stones composed of calcium oxalate, and calcium phosphate, alone or as a mixture. Patients producing pure calcium oxalate stones (< 0·1% phosphate) had a higher oxalate, and lower calcium excretion than stone-free subjects and patients forming other stone types. In contrast, patients producing calcium oxalate stones containing phosphate, even in trace amounts (> 0·1%) had no increase in oxalate excretion, but a higher calcium excretion than stone-free subjects. We could not correlate any computed variable (e.g. AP(CaOx) index) to stone composition. We conclude that pure CaOx stones may be the result of a high oxalate excretion, and that other calcium containing stones may have another and probably more complex aetiology, including primary precipitation of calcium phosphates.

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H, Upadhyaya. "Impact of Calcium Phosphate Nanoparticles on Rice Plant." Journal of Plant Science and Phytopathology 1, no. 1 (2017): 001–10. http://dx.doi.org/10.29328/journal.jpsp.1001001.

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Vecbiskena, Linda, Luigi de Nardo, and Roberto Chiesa. "Nanostructured Calcium Phosphates for Biomedical Applications." Key Engineering Materials 604 (March 2014): 212–15. http://dx.doi.org/10.4028/www.scientific.net/kem.604.212.

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This work is focused on the phase transformation from amorphous calcium phosphate (ACP) to nanostructured hydroxyapatite (HA) or tricalcium phosphate (TCP). Amorphous calcium phosphates with Ca/P molar ratio near 1.67 and 1.5 were synthesized by wet-chemical precipitation method and treated with ethanol. Upon thermal treatment, ACP clusters about 50 nm create a nanostructured HA or TCP. The highlights of this research: The precipitate treatment with ethanol provided a pure α-TCP that was found to be stable up to 1000 °C. HA is obtained from the ACP precursor synthesized using also ammonium dihydrogen phosphate.

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Mekmene, Omar, Thierry Rouillon, Sophie Quillard, Paul Pilet, Jean-Michel Bouler, Stéphane Pezennec, and Frédéric Gaucheron. "Effects of citrate and NaCl on size, morphology, crystallinity and microstructure of calcium phosphates obtained from aqueous solutions at acidic or near-neutral pH." Journal of Dairy Research 79, no. 2 (April 19, 2012): 238–48. http://dx.doi.org/10.1017/s0022029912000076.

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Precipitation of calcium phosphates occurs in dairy products and depending on pH and ionic environment, several salts with different crystallinity can form. The present study aimed to investigate the effects of NaCl and citrate on the characteristics of precipitates obtained from model solutions of calcium phosphate at pH 6·70 maintained constant or left to drift. The ion speciation calculations showed that all the starting solutions were supersaturated with respect to dicalcium phosphate dihydrate (DCPD), octacalcium phosphate (OCP) and hydroxyapatite (HAP) in the order HAP>OCP>DCPD. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses of the precipitates showed that DCPD was formed at drifting pH (acidic final pH) whereas poor crystallised calcium deficient apatite was mainly formed at constant pH (6·70). Laser light scattering measurements and electron microscopy observations showed that citrate had a pronounced inhibitory effect on the crystallisation of calcium phosphates both at drifting and constant pH. This resulted in the decrease of the particle sizes and the modification of the morphology and the microstructure of the precipitates. The inhibitory effect of citrate mainly acted by the adsorption of the citrate molecules onto the surfaces of newly formed nuclei of calcium phosphate, thereby changing the morphology of the growing particles. These findings are relevant for the understanding of calcium phosphate precipitation from dairy byproducts that contain large amounts of NaCl and citrate.

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Irfa’i1, M. A., A. Prihanto, S. Muryanto, R. Ismail, J. Jamari, and A. P. Bayuseno. "CALCINATION AND HYDROTHERMAL PROCESSING OF BOVINES BONES FOR CALCIUM PHOSPHATES EXTRACTION." RASAYAN Journal of Chemistry 16, no. 03 (2023): 1525–33. http://dx.doi.org/10.31788/rjc.2023.1638427.

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Bovine bone is a natural resource having valuable calcium phosphate compounds as a potential bioceramics powder feedstock. This study manipulated the calcium phosphates via hydrothermal processes after calcium phosphatecontaining bone was calcined and extracted. Here the resulting powder precursors obtained after calcining at 900 °C for 5 hours were hydrothermally processed for varying times at 110°C (1–5 h), yielding mainly biphasic calcium phosphates (-tricalcium phosphate and hydroxyapatite) formation with a minute lime according to XRD analysis. Calcination and hydrothermal processing can effectively produce a high amount of hydroxyapatite proportion (> 99 wt.%) with nano crystallite sizes (30-50 nm). After 5-hour calcination, the SEM images revealed the powder product with size uniformity (1 µm) and plate-like morphology. The powdered bovine bone was then subjected to DTA, DTG, and TG analyses to determine its thermal behavior. Calcination temperatures from 300 to 600 OC removed organic compounds and other impurities from powder matrices. Instead, the calcination of bovine bone at temperatures from 800 to 1000 OC supported the result of the stabilized microstructure of calcium-phosphate-bearing minerals, which would make valuable powder feedstock for hydrothermal synthesis. Results of the study demonstrated that simple calcination and subsequent hydrothermal processing of bovine bone providing major hydroxyapatite and minor - tricalcium phosphate would get a depth insight into calcium phosphate resource recovery and recycling.

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Babic-Ivancic, Vesna, and Maja Dutour-Sikiric. "Physico-chemical properties of calcium phosphates." Serbian Dental Journal 59, no. 1 (2012): 7–21. http://dx.doi.org/10.2298/sgs1201007b.

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Calcium phosphates have important role in biological and pathological mineralization. While only one of calcium phosphates, carbonate apatite, represents the main mineral component of teeth and bones, octacalcium phosphate, calcium hydrogenphosphate dihydrate and beta-tricalcium phosphate occur in pathological deposits. From the stand-point of chemists, processes of biological and pathological mineralization could be considered as deposition of inorganic phase within organic matrix, i.e. formation of inorganic-organic composites. Although this approach is very simplified at first glance, it allows clarification of important issues related to biomineralization (e.g. what is the role of individual components of organic matrix in the emerging solid tissue), and design and preparation of new materials for hard tissue regeneration (e.g. process of transformation after implantation). The importance of investigation about calcium phosphates will be presented through the overview of basic physico-chemical reactions related to the formation and transformation of biologically relevant calcium phosphates and their interaction with various organic additives in the laboratory.

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Elliott, J. C. "Calcium Phosphate Biominerals." Reviews in Mineralogy and Geochemistry 48, no. 1 (January 1, 2002): 427–53. http://dx.doi.org/10.2138/rmg.2002.48.11.

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Nancollas, G. H., and S. J. Zawacki. "Calcium Phosphate Mineralization." Connective Tissue Research 21, no. 1-4 (January 1989): 239–46. http://dx.doi.org/10.3109/03008208909050013.

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Dadhich, Prabhash, and Santanu Dhara. "Calcium phosphate flowers." Materials Today 20, no. 10 (December 2017): 657–58. http://dx.doi.org/10.1016/j.mattod.2017.10.009.

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Hawley, Carmel. "Calcium × phosphate product." Nephrology 11 (April 2006): S206—S208. http://dx.doi.org/10.1111/j.1440-1797.2006.00645.x.

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Kanzaki, Noriko, Gabin Treboux, Kazuo Onuma, Sadao Tsutsumi, and Atsuo Ito. "Calcium phosphate clusters." Biomaterials 22, no. 21 (November 2001): 2921–29. http://dx.doi.org/10.1016/s0142-9612(01)00039-4.

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Kingston, Robert E., Claudia A. Chen, and Hiroto Okayama. "Calcium Phosphate Transfection." Current Protocols in Neuroscience 1, no. 1 (November 1997): A.1C.1—A.1C.8. http://dx.doi.org/10.1002/0471142301.nsa01cs01.

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Kondo, Daisuke, Tomohiko Yoshioka, Toshiyuki Ikoma, Kensuke Takamatsu, Kunihiro Ohta, and M. Tanaka. "Electrolytic Deposition of Calcium Phosphates Films on Nitinol Stents." Key Engineering Materials 529-530 (November 2012): 243–46. http://dx.doi.org/10.4028/www.scientific.net/kem.529-530.243.

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Calcium phosphates films were deposited onto pipes and stents of nitinol alloys by an electrolytic deposition (ELD) method. Monocalcium phosphate (Ca (H2PO4)2·H2O) solutions were used as the electrolyte, and electric depositions were carried out at the constant cathode current of 1.59 mA/cm2 at 65°C for 60 min. From the deposition on nitinol pipes, deposition rates were changed in 15 minutes and the precipitates were identified to be octacalcium phosphate (Ca8H2(PO4)6·5H2O) and dicalcium phosphate anhydrous (CaHPO4). The electrolytic depositions on the nitinol alloys were useful for the formation of calcium phosphates films on the complex shape of stents.

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Lawson, A. C., and J. T. Czernuszka. "Collagen-calcium phosphate composites." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 212, no. 6 (June 1, 1998): 413–25. http://dx.doi.org/10.1243/0954411981534187.

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There is a widespread clinical need for bone augmentation and replacement. The major solid phases of bone are collagen and calcium phosphate and a bone analogue based on these two constituents should have some useful properties. In this review this theme is developed and the properties of natural and naturally based composites are compared. Composites have been produced by the precipitation of calcium phosphates on to collagen and a summary of the methods and results from mechanical testing and scanning electron microscopy are presented. Composites with mechanical properties intermediate between cancellous and cortical bone have been produced. The review concludes by explaining some of the mechanical properties of the composites, using knowledge of the hierarchical architecture of bone and results from microscopical examination of the fractured composites.

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Rokidi, Stamatia, Christèle Combes, and Petros G. Koutsoukos. "The Calcium Phosphate−Calcium Carbonate System: Growth of Octacalcium Phosphate on Calcium Carbonates." Crystal Growth & Design 11, no. 5 (May 4, 2011): 1683–88. http://dx.doi.org/10.1021/cg101602a.

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Cave, M. R., David Farrar, and Adrian J. Wright. "Organic/Inorganic Hybrid Calcium Phosphate Biomaterials." Key Engineering Materials 361-363 (November 2007): 383–86. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.383.

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Calcium alkyl phosphates and their strontium and magnesium analogues were synthesised by the reaction of aqueous metal salts with a range of alkyl phosphates of varying chain length and were characterised by X-ray diffraction, thermogravimetric and FTIR analyses. These hybrid structures are based on alternating organic/metal phosphate regions and were found to exhibit a linear increase in interlayer separation upon increasing the length of the alkyl chain. Our analysis suggests a general formula for these phases of M(ROPO3).nH2O (where M = Ca, Sr, Mg and R = alkyl group), containing alkyl bilayers reminiscent of phospholipid bilayers found in biological membranes.

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&NA;. "Monosodium phosphate/disodium phosphate/calcium/diclofenac." Reactions Weekly &NA;, no. 1415 (August 2012): 36. http://dx.doi.org/10.2165/00128415-201214150-00129.

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36

Sugama, Toshifumi, and N. R. Carciello. "Sodium phosphate-derived calcium phosphate cements." Cement and Concrete Research 25, no. 1 (January 1995): 91–101. http://dx.doi.org/10.1016/0008-8846(94)00117-h.

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Le Mare, P. H. "Rock Phosphates in Agriculture." Experimental Agriculture 27, no. 4 (October 1991): 413–22. http://dx.doi.org/10.1017/s0014479700019396.

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SUMMARYThe principles that control effectiveness of rock phosphates as fertilizer are now fairly well understood so that the potential effect of a material can be predicted with some confidence from laboratory analysis of the raw material. Soil characteristics, especially acidity, and calcium and phosphate status, are important: if these are not conducive to dissolution, crop response to rock phosphate is small. Some crop characteristics, especially the extent of root systems and whether they are infected with mycorrhizae, also affect utilization of rock phosphate. Dissolution of rock phosphates may be too slow for rapidly growing crops but may be adequate for perennial crops.Such factors limit the use of rock phosphates for direct application, so that much greater knowledge of the characteristics of the phosphates, soils and crops, and their interactions, is necessary for their successful use than for the soluble phosphates. Economic considerations are important also. Because the phosphate content is less than that of concentrated soluble fertilizers, the cost of transporting rock phosphates, per unit of phosphorus, may not be economic. However, for acid and calcium deficient soils the larger amounts of calcium that rock phosphates supply may be an advantage and may lessen or eliminate the need for lime, especially for crops that require relatively large amounts of calcium.Fosfatos de roca en la agricultura

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38

Crossley, I., K. Swann, E. Chambers, and M. Whitaker. "Activation of sea urchin eggs by inositol phosphates is independent of external calcium." Biochemical Journal 252, no. 1 (May 15, 1988): 257–62. http://dx.doi.org/10.1042/bj2520257.

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We investigated the contribution of external calcium ions to inositol phosphate-induced exocytosis in sea urchin eggs. We show that: (a) inositol phosphates activate eggs of the sea urchin species Lytechinus pictus and Lytechinus variegatus independently of external calcium ions; (b) the magnitude and duration of the inositol phosphate induced calcium changes are independent of external calcium; (c) in calcium-free seawater, increasing the volume of inositol trisphosphate solution injected decreased the extent of egg activation; (d) eggs in calcium-free sea water are more easily damaged by microinjection; microinjection of larger volumes increased leakage from eggs pre-loaded with fluorescent dye. We conclude that inositol phosphates do not require external calcium ions to activate sea urchin eggs. This is entirely consistent with their role as internal messengers at fertilization. The increased damage caused to eggs in calcium-free seawater injected with large volumes may allow the EGTA present in the seawater to enter the egg and chelate any calcium released by the inositol phosphates. This may explain the discrepancy between this and earlier reports.

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Lapeyrie, F., J. Ranger, and D. Vairelles. "Phosphate-solubilizing activity of ectomycorrhizal fungi in vitro." Canadian Journal of Botany 69, no. 2 (February 1, 1991): 342–46. http://dx.doi.org/10.1139/b91-046.

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An easy to use method is presented here to compare and study the mineral phosphate-solubilizing activity of ectomycorrhizal fungi. This technique can discriminate between strains with differing phosphate-solubilizing activities. Synthetic mineral phosphates, crystalline or amorphous, were differentially solubilized by 10 ectomycorrhizal fungi. Natural crystalline phosphates studied do not seem to be solubilized by fungi under similar experimental conditions. Paxillus involutus 1 appears to be able to solubilize calcium phosphates using either ammonium or nitrate nitrogen, but the other isolates were able to effectively solubilize phosphate only in the presence of ammonium. This has implications regarding the possible mechanism used to solubilize phosphate by these isolates. Recrystallization can be seen in the culture medium if calcium ions are present. The type of crystals depends on the phosphate source and on the fungal strain. This technique is suitable for screening a large number of ectomycorrhizal strains. The significance of phosphate-solubilizing activity to plant growth stimulation needs to be determined by field trials. Key words: ectomycorrhizal fungus, phosphate, solubilization.

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GORDIENKO, Katerina, Yaroslav RADOVENCHYK, Tamara KRYSENKO, and Vyacheslav RADOVENCHYK. "EFFICIENCY OF PLANTING CALCIUM IONS FROM DILUTE AQUEOUS SOLUTIONS IN THE FORM OF PHOSPHATES." Herald of Khmelnytskyi National University. Technical sciences 313, no. 5 (October 27, 2022): 134–40. http://dx.doi.org/10.31891/2307-5732-2022-313-5-134-140.

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The specifics of calcium phosphate formation process during diluted aqueous solutions softening for home or office were researched. Studies have shown that, unlike calcium carbonate, effective precipitation of calcium ions with phosphate is possible even at doses less than stoichiometric. The ratio between concentrations of phosphate ions and calcium ions K = [PO43-, mg-eq] / [Ca2+, mg-eq] is a determining factor. Already at K = 0.5 there is a decrease in the content of calcium ions by more than half. In stoichiometry (K = 1), the residual concentrations of calcium ions in the treated water fall below 1 mg-eq/dm3. At K > 1.5, the content of calcium ions in the treated water stabilizes at the level of 0.2 – 0.1 mg-eq/dm3. Water temperature does not significantly affect the deposition of calcium ions with phosphates. A noticeable decrease in efficiency is recorded only at a temperature of 5 ° C. But even in this case, this decrease is 0.1 – 1.5 mg-eq/dm3, which is quite acceptable for living conditions, since it provides soft and very soft water. The reaction between calcium ions and phosphates is quite complete in the first minutes of contact. The settling of mixed solutions for an hour showed that the reaction of the formation of a solid phase takes place at the time of draining the solutions and over time the residual hardness of the water practically does not change. From the point of view of softening efficiency, phosphate is quite suitable as a reagent for removing calcium ions from hard natural waters. An important aspect of the softening technology is the separation of the precipitate formed from the treated water. To do this, it is necessary to determine the conditions for the formation of a crystalline, most compact and formed precipitate. The clarification of the hard water sample treated with sodium phosphate showed that there was no significant difference in deposition at different initial pH values.

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Teixeira, S., S. M. Oliveira, M. P. Ferraz, and F. J. Monteiro. "Three Dimensional Macroporous Calcium Phosphate Scaffolds for Bone Tissue Engineering." Key Engineering Materials 361-363 (November 2007): 947–50. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.947.

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Calcium phosphate ceramics are widely used as bone substitutes since they are biocompatible and bioactive. Having a chemical composition close to natural bone, calcium phosphate ceramics are promising bone substitute materials in orthopaedics, maxillofacial surgery and dentistry. Hydroxyapatite (HA) and tricalcium phosphate (TCP) are the most commonly used calcium phosphates, because their calcium/phosphorus (Ca/P) ratios are close to that of natural bone and they are relatively stable in physiological environment. HA is a major constituent of bone materials and is resorbed after a long time of residence in the body. In this work, highly porous hydroxyapatite scaffolds were produced by polymer replication method and their properties evaluated by Scanning Electron Microscopy (SEM) and micro computerized tomography ()-CT).

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Xu, J. L., Khiam Aik Khor, R. Kumar, and P. Cheang. "RF Induction Plasma Synthesized Calcium Phosphate Nanoparticles." Key Engineering Materials 309-311 (May 2006): 511–14. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.511.

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It was a normal phenomena that hydroxyapatite (HA) decomposes into tricalcium phosphate (TCP), tetracalcium phosphate (TTCP), calcium oxide (CaO) and amorphous calcium phosphate (ACP) during the plasma processing step. The present study characterized the phase evolution of calcium phosphates (CaPs) in the nanoparticles synthesized using a radio frequency (RF) induction plasma processing technique. The morphology and microstructure of the CaP nanoparticles were investigated by XRD, SEM, TEM, Raman spectroscopy, FTIR spectroscopy and thermal analysis. It was found that ACP, α-TCP, TTCP and CaO were the main decomposed phases in the nanoparticle. After heat treatment at dicalcium pyrophosphate (β-Ca2P2O7) due to the extreme decomposition of the starting HA during the RF plasma processing step which rapidly solidified into amorphous phase.

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Glazov, I. E., V. K. Krut’ko, O. N. Musskaya, and A. I. Kulak. "Stabilization of the amorphous state of calcium carbonate-phosphates with phosphate ions." Doklady of the National Academy of Sciences of Belarus 66, no. 5 (November 3, 2022): 501–8. http://dx.doi.org/10.29235/1561-8323-2022-66-5-501-508.

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Amorphous calcium carbonate-phosphate with a Ca/P ratio of 1.83 was precipitated from Ca2+, Ca2+, PO3–4, CO2-3 − containing solutions at pH 10 and stabilized by ethanol dehydration and followed by heating at 400 °C. The presence of PO3–4 ions in the structure of amorphous calcium carbonate-phosphate provides its increased resistance to transformation into crystalline phases. Aging in a Ca2+, PO3–4 , CO2-3 − containing mother solution at pH 10 for 4 days promotes the transformation of amorphous calcium carbonate-phosphate into amorphous calcium carbonate-phosphate / carbonated hydroxyapatite / calcite. The combined effect of PO3–4 и CO2-3 − ions in the aquatic environment on the crystallization of amorphous calcium carbonate-phosphate into carbonated hydroxyapatite contributes to a maximum stabilization of the amorphous state that provides a high extent of bioactivity.

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Cañas-Gutiérrez, Ana, Lenka Toro, Cristina Fornaguera, Salvador Borrós, Marlon Osorio, Cristina Castro-Herazo, and David Arboleda-Toro. "Biomineralization in Three-Dimensional Scaffolds Based on Bacterial Nanocellulose for Bone Tissue Engineering: Feature Characterization and Stem Cell Differentiation." Polymers 15, no. 9 (April 24, 2023): 2012. http://dx.doi.org/10.3390/polym15092012.

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Bacterial nanocellulose (BNC) has a negative surface charge in physiological environments, which allows the adsorption of calcium ions to initiate the nucleation of different calcium phosphate phases. The aim of this study was to investigate different methods of mineralization in three-dimensional microporous bacterial nanocellulose with the intention of mimicking the composition, structure, and biomechanical properties of natural bone. To generate the 3D microporous biomaterial, porogen particles were incorporated during BNC fermentation with the Komagataeibacter medellinensis strain. Calcium phosphates (CPs) were deposited onto the BNC scaffolds in five immersion cycles, alternating between calcium and phosphate salts in their insoluble forms. Scanning electron microscopy (SEM) showed that the scaffolds had different pore sizes (between 70 and 350 µm), and their porous interconnectivity was affected by the biomineralization method and time. The crystals on the BNC surface were shown to be rod-shaped, with a calcium phosphate ratio similar to that of immature bone, increasing from 1.13 to 1.6 with increasing cycle numbers. These crystals also increased in size with an increasing number of cycles, going from 25.12 to 35.9 nm. The main mineral phase observed with X-ray diffraction was octacalcium dihydrogen hexakis phosphate (V) pentahydrate (OCP). In vitro studies showed good cellular adhesion and high cell viability (up to 95%) with all the scaffolds. The osteogenic differentiation of human bone marrow mesenchymal stem cells on the scaffolds was evaluated using bone expression markers, including alkaline phosphatase, osteocalcin, and osteopontin. In conclusion, it is possible to prepare 3D BNC scaffolds with controlled microporosity that allow osteoblast adhesion, proliferation, and differentiation.

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de Oliveira, Sara Verusca, Marcus Vinícius Lia Fook, Elaine Patrícia Araújo, Keila Machado Medeiros, Guilherme Portela Rabello, Renata Barbosa, and Edcleide Maria Araújo. "Obtaining Tetracalcium Pohosphate and Hydroxyapatite in Powder Form by Wet Method." Materials Science Forum 660-661 (October 2010): 954–58. http://dx.doi.org/10.4028/www.scientific.net/msf.660-661.954.

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The development of research in the area of advanced materials and tissue engineering has increased greatly in recent years found that bioceramics are outstanding in the replacement and regeneration of bone tissue, mainly formed by the calcium phosphate ceramics. The objective of this research is to obtain the calcium phosphate where Ca/P = 1.67 and 2.0, to observe the formation of phases after having subjected these materials to heat treatment. The calcium phosphate was produced by the wet method using a direct reaction of neutralization and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray microanalysis (EDS). The XRD results confirm the presence of hydroxyapatite phase in the sample with Ca/P = 1.67, where as the phosphates prepared with Ca/P = 2.0 ratio show a combination of hydroxyapatite and phase β- tricalcium phosphate. The micrographs obtained are characteristic of ceramic material called calcium phosphate. EDS confirmed the presence of Ca, P and O in the material.

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Sunarso, Akira Tsuchiya, Riki Toita, Kanji Tsuru, and Kunio Ishikawa. "Enhanced Osseointegration Capability of Poly(ether ether ketone) via Combined Phosphate and Calcium Surface-Functionalization." International Journal of Molecular Sciences 21, no. 1 (December 27, 2019): 198. http://dx.doi.org/10.3390/ijms21010198.

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Biomedical applications of poly(ether ether ketone) (PEEK) are hindered by its inherent bioinertness and lack of osseointegration capability. In the present study, to enhance osteogenic activity and, hence, the osseointegration capability of PEEK, we proposed a strategy of combined phosphate and calcium surface-functionalization, in which ozone-gas treatment and wet chemistry were used for introduction of hydroxyl groups and modification of phosphate and/or calcium, respectively. Surface functionalization significantly elevated the surface hydrophilicity without changing the surface roughness or topography. The cell study demonstrated that immobilization of phosphate or calcium increased the osteogenesis of rat mesenchymal stem cells compared with bare PEEK, including cell proliferation, alkaline phosphatase activity, and bone-like nodule formation. Interestingly, further enhancement was observed for samples co-immobilized with phosphate and calcium. Furthermore, in the animal study, phosphate and calcium co-functionalized PEEK demonstrated significantly enhanced osseointegration, as revealed by a greater direct bone-to-implant contact ratio and bond strength between the bone and implant than unfunctionalized and phosphate-functionalized PEEK, which paves the way for the orthopedic and dental application of PEEK.

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Sokolova, Marina, Andris Putnins, Imants Kreicbergs, and Janis Locs. "Scale-Up of Wet Precipitation Calcium Phosphate Synthesis." Key Engineering Materials 604 (March 2014): 216–19. http://dx.doi.org/10.4028/www.scientific.net/kem.604.216.

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Within current research calcium phosphates were synthesized by wet chemical precipitation method in laboratory and pilot scale reactor. The aim of this work was to study the influence of main technological parameters of wet chemical precipitation synthesis and scale-up of laboratory synthesis. The results showed that it is possible to obtain calcium phosphates with different and reproducible phase compositions such as hydroxyapatite (HAp), β-tricalcium phosphate (β-TCP) and biphasic calcium phosphates (HAp/β-TCP) in pilot scale reactor. Using the method developed it was possible to increase the product yield more than 30 times compared to formerly used laboratory scale method.

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Lertcumfu, Narumon, Parkpoom Jarupoom, Pongthep Arkornsakul, Tawee Tunkasiri, Denis Russell Sweatman, and Gobwute Rujijanagul. "Effects of Calcium Carbonate Synthesized from Cockle Shell on Characteristics of Calcium Phosphate Biphasic." Applied Mechanics and Materials 804 (October 2015): 143–46. http://dx.doi.org/10.4028/www.scientific.net/amm.804.143.

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Calcium phosphate is a biomaterial which exhibits excellent biocompatibility, bioactivity and biodegradability for bone replacement and other medical applications. In the present work, multiphasic calcium phosphate compounds consisting of hydroxyapatite (HAp) and tri-calcium phosphates (TCP) were prepared by a solid state reaction method. Effects of calcium carbonate (CaCO3: ±3-5 wt%) on the properties of the studied powders were investigated where calcium carbonate powder was synthesized from a natural product (cockle shell). The phase formation and morphology of the powders were characterization by many techniques such as XRD, SEM and dynamic light scattering techniques. The results showed that amount of calcium carbonate additive affected on the properties of the studied samples.

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Sirotinkin, V. P., O. V. Baranov, A. Yu Fedotov, and S. M. Barinov. "Control of the phase composition of advanced calcium phosphates using an x-ray diffractometer with a curved position-sensitive detector." Industrial laboratory. Diagnostics of materials 86, no. 6 (June 22, 2020): 29–35. http://dx.doi.org/10.26896/1028-6861-2020-86-6-29-35.

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The results of studying the phase composition of advanced calcium phosphates Ca10(PO4)6(OH)2, β-Ca3(PO4)2, α-Ca3(PO4)2, CaHPO4 · 2H2O, Ca8(HPO4)2(PO4)4 · 5H2O using an x-ray diffractometer with a curved position-sensitive detector are presented. Optimal experimental conditions (angular positions of the x-ray tube and detector, size of the slits, exposure time) were determined with allowance for possible formation of the impurity phases during synthesis. The construction features of diffractometers with a position-sensitive detector affecting the profile characteristics of x-ray diffraction peaks are considered. The composition for calibration of the diffractometer (a mixture of sodium acetate and yttrium oxide) was determined. Theoretical x-ray diffraction patterns for corresponding calcium phosphates are constructed on the basis of the literature data. These x-ray diffraction patterns were used to determine the phase composition of the advanced calcium phosphates. The features of advanced calcium phosphates, which should be taken into account during the phase analysis, are indicated. The powder of high-temperature form of tricalcium phosphate strongly adsorbs water from the environment. A strong texture is observed on the x-ray diffraction spectra of dicalcium phosphate dihydrate. A rather specific x-ray diffraction pattern of octacalcium phosphate pentahydrate revealed the only one strong peak at small angles. In all cases, significant deviations are observed for the recorded angular positions and relative intensity of the diffraction peaks. The results of the study of experimentally obtained mixtures of calcium phosphate are presented. It is shown that the graphic comparison of experimental x-ray diffraction spectra and pre-recorded spectra of the reference calcium phosphates and possible impurity phases is the most effective method. In this case, there is no need for calibration. When using this method, the total time for analysis of one sample is no more than 10 min.

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Kazakova, Gilyana, Tatiana Safronova, Daniil Golubchikov, Olga Shevtsova, and Julietta V. Rau. "Resorbable Mg2+-Containing Phosphates for Bone Tissue Repair." Materials 14, no. 17 (August 26, 2021): 4857. http://dx.doi.org/10.3390/ma14174857.

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Materials based on Mg2+-containing phosphates are gaining great relevance in the field of bone tissue repair via regenerative medicine methods. Magnesium ions, together with condensed phosphate ions, play substantial roles in the process of bone remodeling, affecting the early stage of bone regeneration through active participation in the process of osteosynthesis. In this paper we provide a comprehensive overview of the usage of biomaterials based on magnesium phosphate and magnesium calcium phosphate in bone reconstruction. We consider the role of magnesium ions in angiogenesis, which is an important process associated with osteogenesis. Finally, we summarize the biological properties of calcium magnesium phosphates for regeneration of bone.

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Journal articles on the topic 'Phosphate de calcium'

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