Preparation and Characterization of Porous Poly(Lactic Acid)/Poly(Butylene Adipate-Co-Terephthalate) (PLA/PBAT) Scaffold with Polydopamine-Assisted Biomineralization for Bone Regeneration.

The development of scaffolds that simultaneously provide porous architectures and osteogenic properties is the major challenge in tissue engineering. Herein, a scaffold with high porosity and well interconnected networks, namely poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT), was fabricated using the gas foaming/ammonium bicarbonate particulate leaching technique. Mussel-inspired polydopamine (PDA)-assisted biomineralization generated by two-step simple soaking in dopamine solution and 10× SBF-like solution was performed to improve the material's osteogenicity. Highly porous scaffolds available in less organized opened cell structures with diameters ranging from 10 µm to 100 µm and 200 µm to 500 µm were successfully prepared. The well interconnected porous architectures were observed through the whole thickness of the scaffold. The even deposition of the organic-inorganic bioactive mineralized layer composed of PDA and nano-scale hydroxyapatite (HA) crystals on the scaffold surface was evidenced by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The developed scaffold exhibited high total porosity (84.17 ± 1.29%), a lower surface contact angle (θ = 45.7 ± 5.9°), lower material degradation rate (7.63 ± 2.56%), and a high level of material biocompatibility. The MTT assay and Alizarin Red S staining (ARS) confirmed its osteogenic enhancement property toward human osteoblast-like cells (MG-63). These results clarified that the developed porous PLA/PBAT scaffold with PDA-assisted biomineralization exhibited good potential for application as a biomaterial for bone tissue regeneration and hard tissue engineering.