Journal of Materials Science: Materials in Medicine

, Volume 20, Issue 9, pp 1787–1794 | Cite as

Effects of carbonate on hydroxyapatite formed from CaHPO4 and Ca4(PO4)2O

  • Jacqueline Lee Sturgeon
  • Paul Wencil Brown


Carbonated hydroxyapatites were formed via reactions in NaHCO3/NaH2PO4 solutions from a mixture of particulate tetracalcium phosphate (TetCP) and anhydrous dicalcium phosphate (DCPA). Reactions were followed by determinations of pH and ion concentrations. The solids formed were analyzed by XRD and FTIR. Rates of heat evolution were established by isothermal calorimetry. Reactions in the absence of NaH2PO4 did not reach completion within 24 h. Constitution of reactants to achieve a DCPA-to-NaHCO3 ratio of 1, in conjunction with the presence of NaH2PO4 as a buffer, was found to be optimal for formation of apatite with no remaining reactant. The amount of carbonate incorporated in this apatite was 4–5 wt%. Calorimetry indicated the reaction mechanism to depend on the bicarbonate concentration in solution. The presence of NaH2PO4 was found to increase the reaction rate but decrease the extent of carbonate uptake.


Apatite Dicalcium Phosphate CaHPO4 Carbonate Apatite DCPA 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    LeGeros RZ. Calcium phosphates in oral biology and medicine. Basel: Karger; 1991.Google Scholar
  2. 2.
    Nelson DGA. The influence of carbonate on the atomic-structure and reactivity of hydroxyapalite. J Dent Res. 1981;60:1621–9.PubMedGoogle Scholar
  3. 3.
    Vignoles M, Bonel G, Holcomb DW, Young RA. Influence of preparation conditions on the composition of Type-B carbonated hydroxyapatite and on the localization of the carbonate ions. Calcif Tissue Int. 1988;43:33–40.PubMedCrossRefGoogle Scholar
  4. 4.
    Rey C, Collins B, Goehl T, Dickson IR, Glimcher MJ. The carbonate environment in bone mineral: a resolution-enhanced Fourier-transform infrared-spectroscopy study. Calcif Tissue Int. 1989;45:157–64.PubMedCrossRefGoogle Scholar
  5. 5.
    Elliot JC. Structure and chemistry of the apatites and other calcium orthophosphates. Amsterdam: Elsevier; 1994.Google Scholar
  6. 6.
    Gibson IR, Bonfield W. Novel synthesis and characterization of an AB-type carbonate-substituted hydroxyapatite. J Biomed Mater Res. 2002;59:697–708.PubMedCrossRefGoogle Scholar
  7. 7.
    Greish YE, Brown PW. Phase evolution during the formation of stoichiometric hydroxyapatite at 37.4°C. J Biomed Mater Res Appl Biomater. 2003;67B:632–7.CrossRefGoogle Scholar
  8. 8.
    Martin RI, Brown PW. Aqueous formation of hydroxyapatite. J Biomed Mater Res. 1997;35:299–308.PubMedCrossRefGoogle Scholar
  9. 9.
    Brown PW, Hocker N, Hoyle S. Variations in solution chemistry during the low-temperature formation of hydroxyapatite. J Am Ceram Soc. 1991;74:1848–54.CrossRefGoogle Scholar
  10. 10.
    Martin RI, Brown PW. Formation of hydroxyapatite in serum. J Mater Sci: Mater Med. 1994;5:96–102.CrossRefGoogle Scholar
  11. 11.
    Miyamoto Y, Toh T, Ishikawa K, Yuasa T, Nagayama M, Suzuki K. Effect of added NaHCO3 on the basic properties of apatite cement. J Biomed Mater Res. 2001;54:311–9.PubMedCrossRefGoogle Scholar
  12. 12.
    Martin RI, Brown PW. Mechanical-properties of hydroxyapatite formed at physiological temperature. J Mater Sci: Mater Med. 1995;6:138–43.CrossRefGoogle Scholar
  13. 13.
    Demaeyer EAP, Verbeeck RMH. Possible substitution mechanism for sodium and carbonate in calciumhydroxyapatite. Bull Soc Chim Belg. 1993;102:601–9.Google Scholar
  14. 14.
    Martin RI, Brown PW. Hydration of tetracalcium phosphate. Adv Cement Res. 1993;5:119–25.Google Scholar
  15. 15.
    Barralet J, Best S, Bonfield W. Carbonate substitution in precipitated hydroxyapatite: an investigation into the effects of reaction temperature and bicarbonate ion concentration. J Biomed Mater Res. 1998;41:79–86.PubMedCrossRefGoogle Scholar
  16. 16.
    LeGeros RZ, Trautz OR, Legeros JP, Klein E. Apatite crystallites: effects of carbonate on morphology. Science. 1967;155:1409–11.PubMedCrossRefADSGoogle Scholar
  17. 17.
    Fulmer MT, Brown PW. Effects of Na2HPO4 and NaH2PO4 on hydroxyapatite formation. J Biomed Mater Res. 1993;27:1095–102.PubMedCrossRefGoogle Scholar
  18. 18.
    Apfelbaum F, Diab H, Mayer I, Featherstone JDB. An FTIR study of carbonate in synthetic apatites. J Inorg Biochem. 1992;45:277–82.CrossRefGoogle Scholar
  19. 19.
    Krajewski A, Mazzocchi M, Buldini PL, Ravaglioli A, Tinti A, Taddei P, et al. Synthesis of carbonated hydroxyapatites: efficiency of the substitution and critical evaluation of analytical methods. J Mol Struct. 2005;744:221–8.CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringThe Pennsylvania State UniversityUniversity ParkUSA

Personalised recommendations