Biofabrication of hybrid bone scaffolds using a dual-nozzle bioplotter and in-vitro study of osteoblast cell

Abstract

Most bone scaffolds made of single biomaterial resulting in limited compressive strength and single property of cell adhesive. In this study, sandwich structures of the bone scaffold with different biomaterials are fabricated to mimic the mechanical properties of human bone. The fabricated scaffolds are also evaluated the cellular efficacy by cell culturing. In this study, biopolymer (mPEG-PCL-mPEG) is synthesized. Biocomposite is made of blending biopolymer with nano-hydroxyapatite (nHA). Both biomaterials are used to form the bone scaffolds with average pore size of 300μm using the developed dual-nozzle bioplotter system. Hybrid scaffolds with sandwich structures are proposed and fabricated. All scaffolds are underwent the compressive and microhardness test for comparing the mechanical properties with human bone. Furthermore, a mouse pre-osteoblast MC3T3-E1cell line is seeded onto fabricated scaffolds and cultured for 28 days for validating the biocompatibility and evaluating the cellular efficacy using methylthiazol tetrazolium (MTT) assay. Biocomposite scaffold has the highest ultimate compressive strength and microhardenss among the others. Ultimate compressive strength and microhardness of fabricated scaffold in vertical build plane are higher than those in horizontal build plane. Sandwich architecture of hybrid bone scaffold with biocomposite outer layer and biopolymer inner layer can improve cell adhesive and cellular efficacy.