Mg- and/or Sr-doped tricalcium phosphate/bioactive glass composites: synthesis, microstructure and biological responsiveness

Mater Sci Eng C Mater Biol Appl. 2014 Sep:42:312-24. doi: 10.1016/j.msec.2014.05.047. Epub 2014 May 24.

Abstract

Presently, there is an increasing interest towards the composites of calcium phosphates, especially β-tricalcium phosphate (TCP), and bioactive glasses. In the present contribution, the recently developed BG_Ca/Mix glass has been used because its low tendency to crystallize allows to sinter the composites at relatively low temperature (i.e. 850°C), thus minimizing the glass devitrification and the interaction with TCP. A further improvement is the introduction of lab-produced TCP powders doped with specific ions instead of non-doped commercial powders, since the biological properties of materials for bone replacement can be modulated by doping them with certain metallic ions, such as Mg and Sr. Therefore, novel binary composites have been produced by sintering the BG_Ca/Mix glass with the addition of pure, Mg-substituted, Sr-substituted or Mg/Sr bisubstituted TCP powders. After an accurate characterization of the starting TCP powders and of the obtained samples, the composites have been used as three-dimensional supports for the culture of mouse calvaria-derived pre-osteoblastic cells. The samples supported cell adhesion and proliferation and induced promising mechanisms of differentiation towards an osteoblastic phenotype. In particular, the Mg/Sr bi-doped samples seemed to better promote the differentiation process thus suggesting a combined stimulatory effect of Mg(2+) and Sr(2+) ions.

Keywords: Bioactive glass; Composites; Dopants; Magnesium; Strontium; β-Tricalcium phosphate.

MeSH terms

  • Animals
  • Biocompatible Materials / chemistry*
  • Biocompatible Materials / pharmacology*
  • Calcium Phosphates / chemistry*
  • Cell Line
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Cells, Cultured
  • Glass / chemistry
  • Hydrogen-Ion Concentration
  • Magnesium / chemistry*
  • Mice
  • Osteoblasts
  • Strontium / chemistry*

Substances

  • Biocompatible Materials
  • Calcium Phosphates
  • Magnesium
  • tricalcium phosphate
  • Strontium