Ultrasmall zinc oxide nanoparticle-reinforced chitosan-fucoidan scaffolds for enhanced antibacterial activity and accelerated osteogenesis

Biomaterials derived from natural polymers have raised much attention for use in bone tissue engineering applications because of their high mechanical strength and biocompatibility. However, challenges persist in developing bone materials with the requisite physicochemical and osteogenic properties. In this study, the freeze-drying method fabricated a scaffold using chitosan and fucoidan reinforced with zinc oxide nanoparticles (CSFU@ZnO). The scaffolds were characterized and evaluated for their osteogenic differentiation, proliferation, and viability of pre-osteoblast cells (MC3T3-E1). Field emission-scanning electron microscopy analysis revealed a porous morphology with interconnected pores and hydrogen bond interaction between chitosan and fucoidan, as confirmed by Fourier transform infrared spectroscopy analysis. The combination of fucoidan with chitosan improved the mechanical properties, swelling capacity, and degradability. The CSFU@ZnO scaffold effectively inhibited the growth of S. aureus and E. coli , as shown by a zone of inhibition assay. In vitro studies revealed enhanced MC3T3-E1 viability, proliferation, and adhesion, as validated by SEM analysis. The osteogenic differentiation of the CSFU@ZnO scaffold showed increased alkaline phosphatase activity, better protein adsorption, and improved bone mineralization compared to the chitosan scaffold. These findings suggest that the ZnO nanoparticle-incorporated chitosan and fucoidan scaffold could be a good and viable material for bone tissue engineering.