Membranes for Bone Engineering Enriched with Magnesium- and Strontium-Substituted Hydroxyapatite

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Materials Science

Background:

• Hydroxyapatite (HA) is crucial for bone regeneration.
• Incorporating magnesium (Mg2+) and strontium (Sr2+) into HA may enhance its osteogenic potential.
• Developing effective scaffolds is key for delivering biomaterials to promote bone healing.

Purpose of the Study:

• To synthesize and characterize Mg2+ and/or Sr2+ substituted HA.
• To create electrospun scaffolds combining poly-l-lactide (PLLA) with modified HA.
• To evaluate the osteoinductive and osteoconductive capacity of these scaffolds using human periodontal ligament stem cells (hPDLSC).

Main Methods:

• Synthesis of HA with Mg2+ and/or Sr2+ substitution, confirmed by X-ray diffraction and SEM.
• Fabrication of PLLA-HA scaffolds via electrospinning.
• In vitro evaluation of hPDLSC proliferation, differentiation, and gene expression in osteogenic and clonogenic media.

Main Results:

• Ionic substitutions in HA did not affect hPDLSC adhesion or proliferation.
• Scaffolds with substituted HA showed increased extracellular mineralization in clonogenic medium.
• Scaffolds containing HA with magnesium exhibited higher osteopontin expression.
• In osteogenic medium, HA with dual ion substitution showed enhanced osteopontin expression and mineralization.

Conclusions:

• Membranes incorporating HA doped with both magnesium and strontium (HA_Mg_Sr) demonstrate superior osteogenic properties.
• These scaffolds promote hPDLSC differentiation, even under clonogenic conditions.
• HA_Mg_Sr scaffolds represent a promising biomaterial for bone regeneration applications.