Biomimetic, Stiff, and Adhesive Periosteum with Osteogenic-Angiogenic Coupling Effect for Bone Regeneration.

Current periosteal grafts have limitations related to low mechanical strength, tissue adhesiveness, and poor osteogenesis and angiogenesis potential. Here, a periosteum mimicking bone aid (PMBA) with similar structure and function to natural periosteum is developed by electrospinning photocrosslinkable methacrylated gelatin (GelMA), l-arginine-based unsaturated poly(ester amide) (Arg-UPEA), and methacrylated hydroxyapatite nanoparticles (nHAMA). Such combination of materials enhances the material mechanical strength, favors the tissue adhesion, and guarantees the sustained activation of nitric oxide-cyclic guanosine monophosphate (NO-cGMP) signaling pathway, with well-coordinated osteogenic-angiogenic coupling effect for accelerated bone regeneration. This work presents a proof-of-concept demonstration of thoroughly considering the progression of implant biomaterials: that is, the initial material components (i.e., GelMA, Arg-UPEA, and nHAMA) equip the scaffold with suitable structure and function, while its degradation products (i.e., Ca2+ and l-arginine) are involved in long-term mediation of physiological activities. It is envisioned that the strategy will inspire the design of high-performance bioscaffolds toward bone and periosteum tissue engineering.