Next Article in Journal
A Novel Method for Culturing of Leptothrix sp. Strain OUMS1 in Natural Conditions
Previous Article in Journal
Biochemical Change at the Setting-up of the Crossed-Lamellar Layer in Nerita undata Shell (Mollusca, Gastropoda)
Article Menu

Export Article

Open AccessArticle
Minerals 2012, 2(2), 100-117;

Dehydration and Rehydration of Carbonated Fluor- and Hydroxylapatite

Department of Chemistry, Franklin & Marshall College, Lancaster, PA 17603, USA
Department of Earth and Planetary Sciences and The Center for Materials Innovation, Washington University in St. Louis, St. Louis, MO 63130-4899, USA
Author to whom correspondence should be addressed.
Received: 12 January 2012 / Revised: 19 March 2012 / Accepted: 21 March 2012 / Published: 30 March 2012
Full-Text   |   PDF [615 KB, uploaded 25 June 2012]   |  


The recent definitive deuterium solid state NMR spectroscopic evidence for structural water in fluor- and hydroxylapatites has prompted our study of the conditions necessary for the removal and reincorporation of this important structural feature of apatites. Thermal gravimetric analysis of 20 synthetic carbonated calcium hydroxylapatite (CCaApOH) samples and nine carbonated calcium fluorapatite (CCaApF) samples has been used to determine the amount of structural and adsorbed water in each sample. No correlation between the weight percent and number of moles of structural water and the weight percent carbonate in CCaApOH and CCaApF has been found. In contrast, there appears to be a relationship between the amount of adsorbed water and the carbonate concentration in the fluorapatites prepared with a two hour digestion time, as well as in the hydroxylapatites prepared with one hour digestion periods, presumably due to the effect of carbonate on crystallite size. Structural water can be removed from the apatite lattice, primarily above 200 °C, but heating to over 550 °C is required for complete removal. This water can be partly reincorporated through an apparently kinetically-controlled process that is enhanced by an increase in time and/or temperature. We speculate that the incorporation of structural water occurs at the beginning of the formation of the apatite structure, approximately coincident with the incorporation of carbonate. We also speculate that water is both removed and reincorporated by proton transfers from water molecules to hydroxide ions. View Full-Text
Keywords: bone structure; carbonated apatite; structural water; dehydration of apatite; rehydration of apatite bone structure; carbonated apatite; structural water; dehydration of apatite; rehydration of apatite

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Share & Cite This Article

MDPI and ACS Style

Yoder, C.; Pasteris, J.; Worcester, K.; Schermerhorn, D.; Sternlieb, M.; Goldenberg, J.; Wilt, Z. Dehydration and Rehydration of Carbonated Fluor- and Hydroxylapatite. Minerals 2012, 2, 100-117.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Minerals EISSN 2075-163X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top