Perormance Optimization And Biocompatibility Of Injectable Silk-hydroxyapatite Bone Materials

Repair of bone defects caused by trauma,infection,tumor or pathological fracture still faces great challenges.Autograft and allograft are mainly used in clinical treatment.Because of the limited availability,and postoperative infection of an autograft,immune rejection,and the epidemic spreading risks of allografts,natural bone grafts are unable to meet the clinical demand.Construction of silk-hydroxyapatite bone materials with biological characteristics similar to normal bone,and showed better osteogenesis capacity through imitating the structure and microenvironment of natural bone.Biomimetic bone materials were developed with silk fibroin-hydroxyapatite nanocomposite hydrogels as the element is a hot in bone repair.Here,angiogenic and oriented cues were introduced to injectable silk-hydroxyapatite nanocomposite hydrogel systems to optimize the properties of the silk fibroin hydroxyapatite injectable bone materialsDesferrioxamine(DFO)was loaded on silk fibroin nanofibers and blended with HA nanoparticles,forming injectable DFO-loaded silk fibroin-HA nanocomposite hydrogels.The composite hydrogels have well mechanical properties and injectable properties,and achieves controlled release of DFO.In vitro and in vivo studies have shown that the composite hydrogels have well vascularization and bone induction properties,and significantly improves bone regeneration capacity.Furthermore,oriented composite hydrogels were prepared by shearing.The in vitro studies showed that the injectable hydrogels capacity were inproved,which lays the foundation for the future in vivo.In conclusion,the present study provided a simple and effective strategy of introducing angiogenic and oriented cues to bone matrices material and provides useful information for the performance optimization of bone materials.