Study On Bone Repair Materials With Excellent Activity Integrated Chinese Medicine Drynariae Rhizoma

In this study, The respective advantages of porcine bone hydroxyapatite (PBHA) and biphasic calcium phosphate (BCP) and chitosan (CS) were combinated together, and they were further modified. The biological activity of materials was improved by optimizing structure of materials themselves. Chinese medicine Drynariae Rhizoma extract (DR) was introduced into bone repair materials for the purpose of good osteoindaction, DR-PBHA-CS,DR-BCP-CS porous biological materials was fabricated by the Vacuum freeze drying method, expecting to induce tissue regeneration not employing living cells and growth factors.The compressive strength of the porous biomaterials and the porosity was tested. The microscopic morphology and components of the biomaterials were analyzed by SEM, XRD and IR, Respectively biological activity of the porous biomaterials were studied by Simulated Body Fluid (SBF) and rabbit in vivo implantation.Results showed that: The compressive strength of the porous biomaterials was enhanced by modifying CS, BCP and PBHA with the coupling agents of NDZ-311 and KH-570, the compressive strength was in the range of 5.6~0.1MPa. The macroporous scaffolds had a feature of high porosity with a pore diameter from 50 to 500μm (mostly 100~200μm). The porosity of the porous biomaterials reached 45%~91% and a good pore connectivity were obtained. With an increasing content of CS, the porosity of the porous biomaterials was gradually increased, the pore structure was cellar-shaped. HA from porcine bone was distributed homogeneously in the pore walls. SBF experiment shows that the porous biomaterials have a good ability to form bone-like apatite, which showed the materials had good bioactivity. The pH values of SBF immersed by composite materials are stable between 6.82~7.42, which showed the materials had good stability. The introduction of the DR speeds up the formation and maturity of new bone by histological observation. The results of rabbit in vivo implantation showed that bone density of bone defect region increased gradually with durity, and bone defect region was substituted by newly formed bone after implantation for four weeks. The porous biomaterials has a good repairng effect when it was transplanted into bone defect. It was concluded that DR-PBHA-CS,DR-BCP-CS porous biomaterials have a good structure properties and a good biological activity. It was suggested that the porous biomaterials could have a potential for bone tissue engineering application.