Fabrication and in vivo osteogenesis of biomimetic poly(propylene carbonate) scaffold with nanofibrous chitosan network in macropores for bone tissue engineering

Abstract

A biomimetic poly(propylene carbonate) (PPC) porous scaffold with nanofibrous chitosan network within macropores (PPC/CSNFs) for bone tissue engineering was fabricated by a dual solid-liquid phase separation technique. PPC scaffold with interconnected solid pore wall structure was prepared by the first phase separation, which showed a high porosity of 91.9% and a good compressive modulus of 14.2 ± 0.56 MPa, respectively. By the second phase separation, nanofibrous chitosan of 50-500 nm in diameter was formed in the macropores with little influence on the pore structure and the mechanical properties of PPC scaffold. The nanofibrous chitosan content was calculated to be 9.78% by elemental analysis. After incubation in SBF for 14 days, more apatite crystals were deposited on the pore surface as well as the nanofibrous chitosan surface of PPC/CSNFs scaffold compared with PPC scaffold. The in vitro culture of bone mesenchymal stem cells showed that PPC/CSNFs scaffold exhibited a better cell viability than PPC scaffold. After implantation in rabbits for 16 weeks, the defect was entirely repaired by PPC/CSNFs scaffold, as opposed to the incomplete healing for PPC scaffold. It indicated that PPC/CSNFs scaffold showed a faster in vivo osteogenesis rate than PPC scaffold. Hereby, PPC/CSNFs scaffold will be a potential candidate for bone tissue engineering.

Chitosan-based scaffolds for bone tissue engineering

“…25, 96 The high surface area-to-volume ratio of nanofibers and the high porosity of nanofiber mats and scaffolds render them promising for a wide range of biomedical applications. Various methods have been utilized to generate polymer nanofibers including phase separation, 97 template-assisted synthesis, 98 self-assembly, 99 drawing, 100 wet spinning, 101, 102 and electrospinning. 103, 104 Electrospinning is a favorable route for fabrication of polymeric nanofibers because the apparatus (Fig.…”

Fabrication and evaluation of electrospun collagen/poly(N-isopropyl acrylamide)/chitosan mat as blood-contacting biomaterials for drug delivery

“…CG, a protein possessing a specific amino acid sequence, size, and structure is a suitable biomaterial for biomedical applications [20]. Use of both CS and CG separately in the drug delivery and biomedical applications has been extensively studied [9,21,22], but they are highly thrombogenic and their use as haemostatic powders or sponges have been reported [23,24].…”

Nanotechnologies in tissue engineering

“…They were able to show good biocompatibility of the scaffolds in vitro as well as in vivo in a subcutaneous rat model as well as an increased osteogenic differentiation of MSCs seeded on the PLA scaffolds. Zhao et al were able to create a porous biomimetic poly(propylene carbonate) (PPC) scaffold with a nanofibrous chitosan network using a dual solid-liquid phase separation technique [9] . In the first phase separation, the PPC scaffold was built, and in the second phase separation, the nanofibrous chitosan structure was prepared in the macropores.…”