Mechanical and biological evaluations of novel electrospun PLLA composite scaffolds doped with oxide ceramics

The objective of this study is to evaluate the in vitro performance of the novel electrospun composite scaffolds that are made of 10% PLLA in binary solvents (75 vol% dichloromethane: 25 vol% acetone) doped with 0.1 wt% of oxide ceramic powders (Hafnium dioxide (HfO₂), titanium dioxide (TiO₂), zirconium dioxide (ZrO₂) and silicon dioxide (SiO₂)). These composite scaffolds were characterized microscopically (SEM, TEM and EDX), mechanically (Vickers hardness and tensile strength) and in in vitro cell studies (biomineralization, protein absorption, and cytocompatibility) with MC3T3 pre-osteoblasts. The combination of PLLA polymer with oxide ceramics was indicated to be able to provide osteogenic properties that can enhance osteoblastic cell proliferation. In particular, results from the study demonstrated that the presence of zirconia and hafnia in the PLLA/ZrO₂ and PLLA/HfO₂ composite scaffolds could increase cell proliferation, protein adsorption and biomineralization properties significantly more than other two groups' scaffolds. PLLA/TiO₂ provided the best mechanical strength than others (p < 0.05). To conclude, the novel composite scaffolds, which are promising biomaterials for tissue engineering, could be manufactured easily by electrospinning techniques.