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Synthesis, characterization and modelling of zinc and silicate co-substituted hydroxyapatite.

Friederichs RJ, Chappell HF, Shepherd DV, Best SM - J R Soc Interface (2015)

Bottom Line: Different scenarios were considered where Zn substituted for different calcium sites or at a 2b site along the c-axis, which was suspected in singly substituted ZnHA.The most energetically favourable site in ZnSiHA was Zn positioned at a previously unreported interstitial site just off the c-axis near a silicate tetrahedron sitting on a phosphate site.A combination of experimental chemistry and DFT modelling provided insight into these complex co-substituted calcium phosphates that could find biomedical application as a synthetic bone mineral substitute.

View Article: PubMed Central - PubMed

Affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK robert.friederichs@gmail.com.

No MeSH data available.


Related in: MedlinePlus

(a) Silicate substitution and a zinc ion replacing a calcium ion. One hydroxyl ion has been removed from the c-axis for charge compensation. The zinc ion is bonded to the hydroxyl ion oxygen atom and one of the silicate ion oxygen atoms. The hydroxyl ion has been pulled off the c-axis. (b) Silicate substitution with a charge compensatory H atom positioned on the silicate ion. The zinc substitution is on the c-axis between two oxygen ions. The hydrogen atom has reattached to one of the c-axis oxygen atoms and the zinc is strongly bonded to both the c-axis oxygen atoms. Oxygen is shown in red, calcium green, phosphorus purple, zinc grey, silicon orange and hydrogen in white. (Online version in colour.)
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RSIF20150190F5: (a) Silicate substitution and a zinc ion replacing a calcium ion. One hydroxyl ion has been removed from the c-axis for charge compensation. The zinc ion is bonded to the hydroxyl ion oxygen atom and one of the silicate ion oxygen atoms. The hydroxyl ion has been pulled off the c-axis. (b) Silicate substitution with a charge compensatory H atom positioned on the silicate ion. The zinc substitution is on the c-axis between two oxygen ions. The hydrogen atom has reattached to one of the c-axis oxygen atoms and the zinc is strongly bonded to both the c-axis oxygen atoms. Oxygen is shown in red, calcium green, phosphorus purple, zinc grey, silicon orange and hydrogen in white. (Online version in colour.)

Mentions: Figure 5a shows the final relaxed structure of the Ca1 substitution. It is clear that there is a rotation of the hydroxyl ion, away from the c-axis and towards the zinc ion.Figure 5.


Synthesis, characterization and modelling of zinc and silicate co-substituted hydroxyapatite.

Friederichs RJ, Chappell HF, Shepherd DV, Best SM - J R Soc Interface (2015)

(a) Silicate substitution and a zinc ion replacing a calcium ion. One hydroxyl ion has been removed from the c-axis for charge compensation. The zinc ion is bonded to the hydroxyl ion oxygen atom and one of the silicate ion oxygen atoms. The hydroxyl ion has been pulled off the c-axis. (b) Silicate substitution with a charge compensatory H atom positioned on the silicate ion. The zinc substitution is on the c-axis between two oxygen ions. The hydrogen atom has reattached to one of the c-axis oxygen atoms and the zinc is strongly bonded to both the c-axis oxygen atoms. Oxygen is shown in red, calcium green, phosphorus purple, zinc grey, silicon orange and hydrogen in white. (Online version in colour.)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4528584&req=5

RSIF20150190F5: (a) Silicate substitution and a zinc ion replacing a calcium ion. One hydroxyl ion has been removed from the c-axis for charge compensation. The zinc ion is bonded to the hydroxyl ion oxygen atom and one of the silicate ion oxygen atoms. The hydroxyl ion has been pulled off the c-axis. (b) Silicate substitution with a charge compensatory H atom positioned on the silicate ion. The zinc substitution is on the c-axis between two oxygen ions. The hydrogen atom has reattached to one of the c-axis oxygen atoms and the zinc is strongly bonded to both the c-axis oxygen atoms. Oxygen is shown in red, calcium green, phosphorus purple, zinc grey, silicon orange and hydrogen in white. (Online version in colour.)
Mentions: Figure 5a shows the final relaxed structure of the Ca1 substitution. It is clear that there is a rotation of the hydroxyl ion, away from the c-axis and towards the zinc ion.Figure 5.

Bottom Line: Different scenarios were considered where Zn substituted for different calcium sites or at a 2b site along the c-axis, which was suspected in singly substituted ZnHA.The most energetically favourable site in ZnSiHA was Zn positioned at a previously unreported interstitial site just off the c-axis near a silicate tetrahedron sitting on a phosphate site.A combination of experimental chemistry and DFT modelling provided insight into these complex co-substituted calcium phosphates that could find biomedical application as a synthetic bone mineral substitute.

View Article: PubMed Central - PubMed

Affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK robert.friederichs@gmail.com.

No MeSH data available.


Related in: MedlinePlus