Electrospun Bio-Nanocomposite Scaffolds for Bone Tissue Engineering by Cellulose Nanocrystals Reinforcing Maleic Anhydride Grafted PLA

Electrospun fibrous bio-nanocomposite scaffolds reinforced with cellulose nanocrystals (CNCs) were fabricated by using maleic anhydride (MAH) grafted poly(lactic acid) (PLA) as matrix with improved interfacial adhesion between the two components. Morphological, thermal, mechanical, and in vitro degradation properties as well as basic cytocompatibility using human adult adipose derived mesenchymal stem cells (hASCs) of MAH grafted PLA/CNC (i.e., MPLA/CNC) scaffolds were characterized. Morphological investigation indicated that the diameter and polydispersity of electrospun MPLA/CNC nanofibers were reduced with the increased CNC content. The addition of CNCs improved both the thermal stability and mechanical properties of MPLA/CNC composites. The MPLA/CNC scaffolds at the 5 wt % CNC loading level showed not only superior tensile strength (more than 10 MPa), but also improved stability during in vitro degradation compared with the MPLA and PLA/CNC counterparts. Moreover, the fibrous MPLA/CNC composite scaffolds were non-toxic to hASCs and capable of supporting cell proliferation. This study demonstrates that fibrous MPLA/CNC bio-nanocomposite scaffolds are biodegradable, cytocompatible, and possess useful mechanical properties for bone tissue engineering.