A co-dispersion nanosystem of graphene oxide @silicon-doped hydroxyapatite to improve scaffold properties

Abstract

Poly l-lactic acid (PLLA) was limited in the further orthopaedic application due to its insufficient mechanical property and poor bioactivity. Graphene oxide (GO) is an effective reinforcement, whereas silicon-doped hydroxyapatite (Si-HA) possesses excellent bioactivity, but either GO or Si-HA tends to aggregate in PLLA matrix. In this study, a [email protected] nanosystem was achieved by in-situ growth of Si-HA on GO, and then incorporated into PLLA scaffold fabricated by laser sintering technology. On one hand, Si-HA on the surface of GO effectively prevented the aggregation of GO by acting as a barrier between GO nanosheets. On the other hand, GO hindered the aggregation of Si-HA by means of anchoring Si-HA. Results displayed that the compressive strength and modulus of the PLLA/[email protected] composite scaffold were enhanced by 85% and 120%, respectively. Meanwhile, the scaffold exhibited significantly improved bioactivity, and consequently promoted cell adhesion, proliferation and differentiation. The developed PLLA/[email protected] composite scaffold with excellent mechanical properties and superior bioactivity could serve as a promising substitute for bone repairing.