Study of calcium phosphate formation driven by the dissolution of a 45S5 bioactive glass

Here, we use and assess an in-situ liquid TEM cell aiming to increase understanding of a particular silicate glass alteration that results in solution-phase hydroxyapatite (HA) like material formation. 1-3

Silicate based bioactive glasses form hydroxyapatite like material interfacial bonding between human tissue and elements such implants, bone grafts, fillings.^4-5 When in contact with an aqueous solution, the release of the bioglass modifying ions and the hydrolysis/condensation of the Si0₂ network drives calcium phosphate (CaP) precipitation and nucleation. The in-situ real-time imaging of this process is being used to study (i) the role of the hydrolysed/condensed silica-gel layer formed on/around bioglass particles in the CaP formation, (ii) if there are any incorporated ions, i.e. sodium, silicon from the bioglass dissolution into the calcium phosphate formed material, (iii) whether this process proceeds by classical or non-classical nucleation steps and (iv) if phase transitions occur can these be observed in real-time.

References

1.         Hench, L. L. Journal of the American Ceramic Society. 1998.

2.         de Jonge, N.; Ross, F. M. Nature nanotechnology. 2011.

3.         Wang, L.; Nancollas, G. H. Chemical reviews. 2008.

4.         Mann, S., 2001.

5.         Jones, J. R. Acta Biomater. 2015.