Novel chitosan/starch scaffold supplemented with hydroxyapatite nanoparticles enhanced mineralization for bone regeneration: processing and characterization

Abstract An ideal bone graft would satisfy both clinical and social criteria; therefore, there is a continuing quest to develop a novel bone scaffold. In this study, a novel 3-dimensional (3D) scaffolds mimicking bone structure were fabricated from chitosan/starch loaded with different amounts of HA nanoparticles (5.0, 7.5 and 10.0% wt./wt. of polymers) using co−precipitation combined with a freeze−drying method in which HA nanoparticles with particle sizes ranging from 60 to 240 nm were generated from chicken bone. Based on SEM micrographs, all the obtained scaffolds presented high and connected porous structures with large pore sizes ranging from 150 to 500 μm; moreover, the presence of HA in the composite scaffolds was confirmed by XRD and EDS analyses. Besides, the porosity and elastic modulus of all the obtained scaffolds were characterized. Specifically, composite scaffolds with HA displayed high biocompatibility in vitro as well as a lower biodegradable rate in both PBS and SBF solutions than did scaffolds from a chitosan/starch matrix; moreover, calcium ions released from the scaffolds provided the effect of HA nanoparticles on biomineralization. The obtained results suggested that chitosan/starch/HA composite scaffolds provide a promising candidate scaffold for BTE application in which HA nanoparticles behave as bioactive components triggering the mineralization of chitosan/starch scaffolds.