“…One is to improve the cell adhesion onto HA-based scaffolds by coating of scaffolds with ECM proteins such as collagen and fibronectin [19] or covalent binding of Arg-Gly-Asp (RGD) to a cross-linked HA [20]. The other one is to develop HA-based hybrid scaffolds in the form of nanofibers, hydrogels, and sponges by combining HA with other biomaterials such as collagen [1,21], gelatin [8,22,23], chitosan [24,25] and silk fibroin [18,26].…”