Fabrication and characterization of 3D-printed biocomposite scaffolds based on PCL and silanated silica particles for bone tissue regeneration

Abstract In this study, we aimed to improve both the mechanical properties and cellular activities of poly(ɛ-caprolactone) (PCL)/silica composite scaffolds by silane modification. We fabricated biocomposite scaffolds using a melt-blending process and 3D bioprinting method (Pure PCL, PSv 5 (5 wt% silica with 95 wt% PCL), PSv 10 (10 wt% silica with 90 wt% PCL), and PSv 20 (20 wt% silica with 80 wt% PCL), respectively). To confirm the performance of this composite scaffold for use as a biomedical scaffold, physical and biological properties were evaluated. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) mappings of the fabricated composite scaffolds revealed that the silica particles were uniformly embedded in the internal PCL struts. In the mechanical test, by reacting the silica with a silane coupling agent, the composite scaffold showed dramatically improved mechanical properties. Especially, Young’s modulus of the PSv 20 scaffold was 1.4 times higher than that of the pure PCL scaffold. In in vitro tests, the proliferation rate in the PSv 20 was about 1.7 times higher than that of the controlled PCL after 7 days of cell culture. Furthermore, calcium mineralization of osteogenic differentiation for the PSv 20 composite scaffold was observed to be 2.9 times greater than that of the pure PCL scaffold. Based on the results, we suggest that 3D printed silane-modified silica containing PCL scaffolds would be suitable for bone regeneration applications or regeneration therapies.