Fabrication of polycaprolactone/chitosan/hydroxyapatite structure to improve the mechanical behavior of the hydrogel-based scaffolds for bone tissue engineering: Biscaffold approach

The main idea of this study is to create a 3D printed scaffold to improve the mechanical behavior of hydrogels for bone tissue engineering. This paper investigated the effects of infill percentage and strand diameter on the 3D printed polycaprolactone/Chitosan/HA scaffold's mechanical properties. The printing parameters were optimized by central composite design in response surface methodology. The X, Y, and Z axes measured stiffness (N/m), compressive strength (MPa), and elongation at break (%). The results showed that the highest stiffness of all samples (in both vertical (65 MPa) and horizontal (32 MPa) loading dimensions) could be found in the scaffolds with 40% infill and the strands with 400 mu m diameter. It was also indicated that the degradability of the samples could be improved (0.33%-1.03%) with a reduction of strand diameter from 600 to 400 mu m. The most swelling was attributed to the scaffold with 50% infill and strand diameter of 600 mu m. Hydrophilicity was improved by employing chitosan (78.3 degrees -66.3 degrees). Results depicted good biocompatibility (>80%) of the samples. To sum up, the idea of a biscaffold with suitable engineering can be a good idea to enhance the mechanical behavior of hydrogel-based scaffolds.