Fabrication and Characterization of 3D Nanostructured Polycaprolactone-Gelatin/Nanohydroxyapatite-Nanoclay Scaffolds for Bone Tissue Regeneration

Numerous clinical bone disorders, such as infections and bone loss from cancer or trauma, increase the need for bone regeneration. Due to the difficulty of self-repairing large bone defects, bone tissue engineering has gained popularity. In this study, polycaprolactone(PCL)-gelatin(GEL) scaffolds with varying concentrations of nanohydroxyapatite (NHA) and nanoclay (NC) particles were fabricated using 3D printing technology, and their physiochemical and biological properties were assessed. PCL has excellent mechanical properties, but its hydrophobicity and long-term degradation limit its utility in scaffold fabrication. Thus, GEL, NHA and NC have been used to improve the overall performance of the polymer such as hydrophilicity, strength, adhesiveness, biocompatibility, biodegradability, and osteoconductivity. The morphological analysis revealed 3D printed structures with rectangular interconnected pores and well-distributed nanoparticles. The highest porosity belonged to PCL-GEL/NHA-NC (30/70) at 69.49%, which may directly contributed to the increase in the compressive modulus and degradation rate. The wettability, compressive strength, water uptake rate, biodegradability, and bioactivity of PCL-GEL scaffolds improved significantly as the NC concentration increased. The behavior of the seeded MG-63 cells on the 3D printed nanocomposite scaffolds was evaluated using the MTT assay, DAPI staining, and SEM micro images. It was discovered that the inclusion of NHA and NC nanoparticles can promote cell proliferation, viability, and adherence. Through the obtained in vitro results, the fabricated 3D printed PCL-GEL/NHA scaffold with higher NC concentration can be regarded as a promising scaffold for expediting the repair of bone defects.