Fabrication and characterization of 3D printed biocomposite scaffolds based on PCL and zirconia nanoparticles

Abstract

The application of three-dimensional printed polymer scaffolds in repairing bone defects is a promising strategy. Among them, polycaprolactone (PCL) scaffolds are widely studied due to their good processability and controlled degradation rate. However, as an alternative graft for repairing bone defects, PCL materials have poor hydrophilicity, which is not conducive to cell adhesion and growth. In addition, the poor mechanical properties of PCL materials cannot meet the strength required to repair bone defects. In this paper, nano-zirconium dioxide (ZrO2) powder is embedded in PCL material through a melt-mixing process, and a regular grid scaffold is constructed by 3D printing. The embedding of nanometer zirconium dioxide powder improves the hydrophilicity and water absorption of the composite scaffold, which is conducive to cell adhesion, proliferation and growth and is beneficial to the exchange of nutrients. Therefore, the PCL/ZrO2 composite scaffold showed better biological activity in vitro. At the same time, the PCL/ZrO2 composite material system significantly improves the mechanical properties of the scaffold. Among them, compared with the pure PCL scaffold, the Young’s modulus is increased by about 0.4 times, and the compressive strength is increased by about 0.5 times. In addition, the osteogenic differentiation results also showed that the PCL/ZrO2 composite scaffold group showed better ALP activity and more effective bone mineralization than the pure PCL group. We believe that the 3D printed PCL/ZrO2 composite scaffold has certain application prospects in repairing bone defects.