Fabricating a novel bioinspiring <scp>3D</scp>‐printed sodium alginate/silk fibroin/polyvinyl alcohol/nano‐hydroxyapatite composite scaffold structure for bone tissue engineering application

Abstract In the present work, we fabricated 3D‐printed biofunctionalized nanocomposite scaffold structures using bioinks prepared by incorporating different concentrations (0.5%–1.5% w/v) of nano‐hydroxyapatite (n‐HA) into optimized a tri‐polymer complex blend comprising of sodium alginate (SA), silk fibroin (SF), polyvinyl alcohol (PVA) with composition represented as SA 70 /SF 30 /PVA 3 , wherein, SA/SF is in 70:30 (v/v) ratio and PVA is in 3% (w/v) ratio. The printed scaffolds consist of microfibers with fiber diameter and pore size range of 437–806 and 389–446 μm having pore interconnecting networks as assessed by scanning electron microscope image analysis. However, with increased n‐HA content, the formation of a microfibrous porous structure with interconnected pores. The amorphous and hydrophilic characteristics of the scaffolds were revealed by XRD analysis and contact angle values ranging from 52 ± 2° to 66 ± 1°. SA 70 /SF 30 /PVA 3 scaffold containing 1.5% (w/v) n‐HA has shown a controlled degradation pattern. The highest compressive strength of 0.193 MPa was shown by SA 70 /SF 30 /PVA 3 /n‐HA 1.5 scaffold. The fabricated scaffolds are cytocompatible, as evident from cell adhesion and MTT assays. Among the scaffolds, the SA 70 /SF 30 /PVA 3 /n‐HA 1.5 scaffold exhibited better biological activities as evaluated by an in vitro cell study. A higher alkaline phosphatase activity signifying superior osteogenic performance of the SA 70 /SF 30 /PVA 3 /n‐HA 1.5 scaffold could be a favorable substitute for bone tissue engineering applications. Highlights Nano hydroxyapatite provided structural stability to the scaffold. Controlled degradation pattern of the fabricated scaffold. Higher compressive strength of the scaffold. Hydrophilic and amorphous nature of the scaffold. The scaffold has a favorable environment for bone tissue regeneration.