On the role of alginate coating on the mechanical and biological properties of 58S bioactive glass scaffolds

Abstract

In this study, novel 3D porous alginate-coated 58S bioactive glass scaffolds were fabricated through a foam replication method using a combination of amorphous 58S bioactive glass structure and sodium alginate. The formation of the alginate coating on the surface of the struts of BG scaffolds was confirmed. The effect of alginate coating on the microstructure, mechanical properties, biodegradability, biomineralization, adhesion, viability, and differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs) on the 58S BG scaffolds were evaluated. A 45.2% increase in hMSC's viability and a 3.4-fold increase in ALP activity of the 1AlBG scaffold in the absence of an osteogenic differentiation media compared to an uncoated BG scaffold were observed. Notably, gene expression analysis exhibited that the 1AlBG scaffold resulted in accelerated osteogenic differentiation of hMSCs, as expression of COL-1, RUNX2, and OCN increased after 14 days. Results revealed a significant increase of antibacterial inhibition in the 1AlBG scaffold in comparison to the BG scaffold. Based on the microstructural, mechanical, and biological investigations, the 1AlBG scaffold exhibited enhanced mechanical and biological properties, making it a promising candidate for bone regeneration. Overall, our findings have highlighted the potential of alginate-coated BG scaffolds to stimulate bone regeneration through stem cell osteoinduction.

Keywords: Alginate coating; Bioactive glass; Bone regeneration.