Fabrication and characterization of mineralized P(LLA-CL)/SF three-dimensional nanoyarn scaffolds

Particular attention has been given to three-dimensional scaffolds for bone tissue regeneration. In this study, poly(l-lactic acid-co-ε-caprolactone) (P(LLA-CL) nanoyarn scaffold and poly(l-lactic acid-co-caprolactone)/silk fibroin (P(LLA-CL)/SF) nanoyarn scaffold were fabricated by a dynamic liquid support electrospinning system; and then the three-dimensional (3D) nanoyarn scaffolds were prepared by freeze-drying processes. The results indicated the average diameter of P(LLA-CL) and P(LLA-CL)/SF nanoyarns were 29.44 ± 3.47 μm and 11.59 ± 0.46 μm, respectively. The yarn in the nanoyarn scaffold was twisted by many nanofibers as evidenced by scanning electron microscope (SEM) result. These nanoyarn scaffolds were biomineralized by alternatively immersing the nanoyarn scaffolds into phosphoric acid and calcium ion solutions. After biomineralization, the existence of hydroxyapatite (HA) particles on the scaffolds was confirmed using fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. In vitro study of cell proliferation was found to be higher on P(LLA-CL)/SF scaffold as compared to P(LLA-CL) scaffold after culturing for 14 days. H&E staining results showed that cells not only attached to the surface of 3D scaffold but also infiltrated into the scaffold. This study indicated that the electrospun P(LLA-CL)/SF scaffold with nanostructure morphology could improve cell adhesion and proliferation and electrospun P(LLA-CL)/SF scaffold with biomineralization has a potential application for bone tissue engineering.