Functionalization of Chitosan-TiO2 Nanotubes Scaffolds with Fibronectin for Bone Regeneration

Composite scaffolds are promising regenerative medicines. Chitosan-TiO2 nanotubes (CTNTs) scaffold as a composite scaffold is, however, associated with low biocompatibility. This research aims to increase in vitro efficacy of CTNTs scaffolds by using fibronectin (FN) and investigate the adsorption affinity of such scaffolds towards FN. CTNTs scaffolds were prepared via direct blending of TiO2 nanotubes (TNTs) and chitosan solution. The mixture was then subjected to 24-h freezing and 24-h freeze drying. The scaffolds were further functionalized with FN solution (20, 40, 60, 80 and 100 μg/mL) via adsorption. The amount of adsorbed FN by the scaffolds was determined via colorimetric method. MG63 was used to evaluate the in vitro efficacy of CTNTs scaffolds with FN. The adsorption affinity of CTNTs scaffolds towards FN was high, as no saturation was achieved. The adsorption isotherm of FN onto CTNTs scaffolds fitted well with Temkin isotherm suggesting there was electrostatic interaction between the scaffolds and FN. Enhanced proliferation and early differentiation were observed in MG63 cultured on CTNTs scaffolds with FN. Particularly, CTNTs scaffolds functionalized with 60 μg/mL FN promoted the highest proliferation and early differentiation. CTNTs scaffolds with FN showed potential as scaffolding material for bone regeneration.