Surface-Modified Graphene Oxide with Compatible Interface Enhances Poly-L-Lactic Acid Bone Scaffold

Abstract

Graphene oxide (GO) usually serves as a reinforce phase in polymer because of its superior mechanical strength and high specific surface area. In this work, GO was grafted with L-lactic acid monomer (denoted as GO@PLLA) to overcome the aggregation in matrix and then incorporated into the poly-L-lactic acid (PLLA) scaffold fabricated by selective laser sintering. In hybrid scaffold, GO@PLLA exhibited uniform dispersion in the matrix. Furthermore, mechanical interlock between GO@PLLA and PLLA matrix formed and reinforced the interface bonding. On the other hand, the heterogeneous distributed GO acted as effective nucleating agent and resultantly enhanced the crystallization. Results showed that the tensile and compressive strength of scaffolds increased by 143.3% and 127.6%, respectively. Meanwhile, the scaffold exhibited an increased degradation rate of 37.9%, which could be attributed to the abundant hydrophilic functional groups on GO. Moreover, the scaffold exhibited favorable bioactivity and biocompatibility. Herein, the developed hybrid scaffold showed potential capacity for bone tissue engineering.