Research On Antibacterial Modified HA-SiO₂ Composite Porous Material For Bone Repair

Tissue engineering is an emerging discipline that has attracted the attention of researchers in recent years.As a hot focus of research in the field of tissue engineering,bone tissue engineering scaffold materials are mainly realized through growth factors,drugs and gene delivery.The material used for the scaffold is required to have a certain mechanical strength and porosity,provide mechanical strength,transfer growth factors and nutrients at the defect site.As the main component of human bones,hydroxyapatite is widely used in bone tissue engineering scaffolds.Based on the above background,in this study,the HA-SiO₂ inorganic composite fiber membrane was prepared by electrospinning technology.Because the fiber membrane does not have antibacterial properties,And using nano-zinc oxide to modify the antibacterial fiber membrane material,successfully prepared ZnO/HA-SiO₂ inorganic composite fiber membrane.The two fiber membranes were used as raw materials to self-assemble the porous composite scaffold.Finally,an animal model was established to study the osteogenic ability of the HA-SiO₂ fiber membrane.The specific research content is as follows:(1)The HA-SiO₂ inorganic composite fiber membrane prepared by electrospinning technology.The addition of HA improves the biological activity of the material,reduces the brittleness of silica,and improves the toughness of the composite fiber membrane material;both pure SiO₂fiber membrane and HA-SiO₂ are non-cytotoxic.The HA-SiO₂ fiber membrane with a molar content of 20%hydroxyapatite degrades linearly,and apatite deposits occur during the degradation process.(2)The research results of hydroxyapatite after antibacterial modification treatment show that nano-zinc oxide adheres to the surface of hydroxyapatite and has good antibacterial properties against Staphylococcus aureus;The study of ZnO/HA-SiO₂ inorganic composite fiber membrane shows that nano-zinc oxide modified hydroxyapatite particles are attached to silica fiber filaments.With the increase of zinc oxide content,large agglomerated particles appear in the fiber membrane.;The fiber membrane has good antibacterial ability to Staphylococcus aureus,and it is not cytotoxic.(3)The size of self-assembled HA-SiO₂ and ZnO/HA-SiO₂ porous composite scaffolds is controllable and can meet the needs of different bone defect sites;ZnO/HA-SiO₂ composite porous scaffolds have high porosity,which is beneficial to nutrient transmission and cells adhesion;Compared with HA-SiO₂ composite porous scaffold,nano-zinc oxide modified hydroxyapatite-silica composite scaffold has higher compressive strength.(4)Animal experiments have studied the ability of HA-SiO₂ fiber membrane to repair and regenerate alveolar bone.The results show that the defect area on the repair side has been bone healed after three weeks.In the defect of alveolar bone,new bone trabecula is formed,and a large amount of collagen is produced in the periodontal soft tissue.PDLSCs/HA-SiO₂ composite fiber membrane can effectively promote the restoration and regeneration of alveolar bone defects.