bioinspired biodegradable, porous and photoactive cellulosic scaffold with antibacterial properties for bone regeneration

Aim and background: bone-related diseases are common clinical problems that result in hardly recoverable bone defects. in this study, mild heat-induced osteogenesis is studied by a biodegradable cellulose-based scaffold coated with bismuth sulfide nanoparticles (nps) while its pores are filled with gelatin-hyaluronic acid thermo-responsive hydrogel. methods: bismuth sulfide nps were prepared using a simple chemical reaction and plant-derived cellulose scaffolds (c-scaffold) were coated with nps entirely to generate bi-scaffold. then the scaffolds were immersed in gelatin-ha hydrogel for 4 hours (bi-gel scaffold). following that, the scaffolds were dried by freeze-drying. results and discussion: the fe-sem images of scaffolds demonstrated that the scaffold coated with nps and impregnated with gel while indicating desirable porosity. the elemental analysis of bi-scaffold confirms that the scaffold coated with bismuth sulfide sufficiently. the compressive strength of bi-gel scaffold is approximately about 17.2 mpa. the photothermal performance of the bi-scaffold showed that the temperature increased rapidly to 76°c after nir laser irradiation at 1.5 w/cm2, which confirm the high photothermal conversion efficiency of the scaffold. the scaffolds showed very potent antibacterial effect against e. coli and s. aureus under nir irradiation. conclusion: the bismuth sulfide coated cellulosic scaffold has great potential in orthopedic applications due to good nir-mediated and hydrogel-assisted osteogenic performances and this study provides new insights into the design and fabrication of new-style osteoimplants for bone regeneration.