Engineering Flexible Nanofibrous Hydroxyapatite Scaffolds With Tunable Degradation and Mechanical Properties for Bone Regeneration

ABSTRACT Although hydroxyapatite (HA) is widely employed in bone regeneration due to its close chemical similarity to native bone and excellent osteoconductive properties, it shares with other conventional ceramics the inherent limitations of brittleness and low resorbability. The aim of this work is to demonstrate that we can convert the traditional brittle and poorly resorbable HA ceramics into flexible scaffolds with tunable stiffness and degradation profiles using ceramic nanofibers (NFs) as structural building blocks. This goal has been tackled by adjusting NFs mass to modulate scaffold stiffness and mechanical strength, and by modifying the NFs synthesis time to produce nanofibers of different sizes, thereby influencing degradation. Flexible scaffolds with stiffness values ranging from 1 to 100 kPa under wet conditions and tailored degradation profiles between 10 and 32 wt.% were achieved. The resulting scaffolds constitute a novel platform for investigating the influence of scaffold stiffness on cellular behavior in the mechanotransduction field.