3D printing of HA / PCL composite tissue engineering scaffolds

Here, the internal structure and mechanical properties of the hydroxyapatite/polycaprolactone scaffolds, prepared by fused deposition modeling (FDM) technique, were explored. Using hydroxyapatite (HA) and polycaprolactone (PCL) as raw materials, nano-HA/PCL and micro-HA/PCL that composite with 20 wt% HA were prepared by melt blending technology, and HA/PCL composite tissue engineering scaffolds were prepared by self-developed melt differential FDM 3D printer. From the observation under microscope, it was found that the prepared nano-HA/PCL and micro-HA/PCL tissue engineering scaffolds have uniformly distributed and interconnected nearly rectangular pores. By observing the cross-sectional view of the nano-HA/PCL scaffold and the micro-HA/PCL scaffold, it is known that the HA particles in the nano-HA/PCL scaffold are evenly distributed and the HA particles in the micro-HA/PCL scaffold are agglomerated, which attribute nano-HA/PCL scaffolds with higher tensile strength and flexural strength than the micro-HA/PCL scaffolds. The tensile strength and flexural strength of the nano-HA/PCL specimens were 23.29 MPa and 21.39 MPa, respectively, which were 26.0% and 33.1% higher than those of the pure PCL specimens. Therefore, the bioactive nano-HA/PCL composite scaffolds prepared by melt differential FDM 3D printers should have broader application prospects in bone tissue engineering.