Poly(ester amide)-Bioactive Glass Hybrid Biomaterials for Bone Regeneration and Biomolecule Delivery

Designing bioactive materials for repairing or regenerating bone defects is an active area of research and discovery. Despite advances made in sol-gel-derived hybrid biomaterials design, three challenges remain: (i) the choice of biodegradable polymers that can form a homogeneous solution in the presence of water is very limited, (ii) low-temperature (below 50 °C) incorporation of calcium into the inorganic matrix while having molecular-level mixing has proven to be a difficult task, and (iii) incorporation of drug-loaded mesoporous nanoparticles into polymer-bioactive glass hybrid scaffolds has not been achieved. In this study, we developed bioactive biomaterials for bone repair/regeneration from an α-amino acid-derived biodegradable poly(ester amide) (PEA) and a tertiary bioglass (SiO₂-CaO-P₂O₅), where calcium was incorporated into the glass network at ambient temperature. Furthermore, drug-loaded functional mesoporous silica nanoparticles prepared by surfactant templating were successfully incorporated into PEA-bioglass porous scaffolds. The resulting homogenous single-phase materials showed deposition of hydroxyapatite on their surfaces, supported mesenchymal stem cell attachment and proliferation, and showed a sustained and slow release of a model compound. Taken together, these biomaterials have the potential to be used as a bifunctional platform for bone regeneration via ion release and biomolecule delivery.