Development of hybrid scaffold with biomimetic 3D architecture for bone regeneration.

In the present study, a biomimetic three-dimensional hybrid scaffold has been designed considering the bone natural architecture with favorable interconnected porous structure, nano-microscale features and mechanical strength. The chief components of the hybrid scaffold are core-sheath nanofibers and hydrogel, suitably arranged to create a bone like microenvironment. Specifically, the core-sheath nanofibers were coiled tightly into a ring to mimic the osteon, and reinforced in a hydrogel matrix. Morphological analysis using SEM and 4D-X-ray microscopy revealed that the hybrid scaffold consists of coiled rings of nanofibers in highly porous hydrogel matrix showing structural similarity to osteons. The reinforcement of electrospun nanofibers in hydrogel influenced the mechanical properties of scaffold. The potential application of the biomimetic hybrid scaffold, and the role of its specific architecture, was subsequently investigated in vitro using a human osteosarcoma fibroblast cell line. Furthermore, DNA quantification, alkaline-phosphatase and alizarin assay validated the potential of fabricated scaffold for bone tissue-regeneration.