Enhanced mineralization of the nanofibers-incorporated aerogels increases mechanical properties of scaffold and promotes bone formation

The poor mechanical performance of the aerogels hampered their potential applications in bone tissue engineering. To reinforce their mechanical properties, an electrospinning nanofibers-incorporated aerogels were fabricated in this study. Here, silk fibroin solution is blended with chitin in various proportions, and then electrospun to produce the hybrid nanofibers. The silk fibroin/chitin hybrid nanofibers were incorporated into the SF-based composite aerogels to enhance their mechanical properties. nHA was deposited onto the surface of the nanofiber-incorporated aerogels via in situ biomineralization, leading to the nanofibers/nHA-reinforced composite aerogels. The as-prepared composite aerogels exhibit favorable mineralization abilities through immersing in simulated body fluid. SEM observation suggested that the mineralization degree of the SF-based aerogels was positively related with the content of electrospinning nanofibers in the composite aerogels. The results obtained from the compress stress-strain curves revealed that the incorporation of nanofibers and in vitro biomineralization of nHA both enhanced the mechanical performance of the composite aerogels. The osteogenic ability of the prepared aerogels was also improved after incorporation of NFSF-0.75%CT and nucleation of nHA in SBF. Therefore, the composite aerogels prepared by the incorporation of NFSF-0.75%CT and immersing into SBF exhibited an enhanced mechanical properties and improved osteogenic ability.