Send to

Choose Destination
Nat Commun. 2013;4:1507. doi: 10.1038/ncomms2490.

Ion-association complexes unite classical and non-classical theories for the biomimetic nucleation of calcium phosphate.

Author information

Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory of Materials and Interface Chemistry and Soft Matter Cryo-TEM Research Unit, PO Box 513, 5600 MB Eindhoven, The Netherlands.


Despite its importance in many industrial, geological and biological processes, the mechanism of crystallization from supersaturated solutions remains a matter of debate. Recent discoveries show that in many solution systems nanometre-sized structural units are already present before nucleation. Still little is known about the structure and role of these so-called pre-nucleation clusters. Here we present a combination of in situ investigations, which show that for the crystallization of calcium phosphate these nanometre-sized units are in fact calcium triphosphate complexes. Under conditions in which apatite forms from an amorphous calcium phosphate precursor, these complexes aggregate and take up an extra calcium ion to form amorphous calcium phosphate, which is a fractal of Ca(2)(HPO(4))(3)(2-) clusters. The calcium triphosphate complex also forms the basis of the crystal structure of octacalcium phosphate and apatite. Finally, we demonstrate how the existence of these complexes lowers the energy barrier to nucleation and unites classical and non-classical nucleation theories.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center