Construction And Study On The Drug Loading Propertu Of Apatite Scaffold Accumulation With Porous Particles

With the increase of the aging of society and various wounds, biological materials, particularly the demand of bone repair material is increasing. There is a large extent depend on the bone graft to repair for larger sized bone defect cannot self-healing defects. HA is the main component of bone mineral phase which lakes 45% of dry bone tissue. It has good biocompatibility and bone conduction, and excellent chemical and biological affinity as well when used as a bone graft material. It can be widely used in biological hard tissue repair, replacement and promotional materials of its functions. The porous structure of biological bone tissue can be maintained to ensure blood flow, the normal metabolism of bone tissue, and also can adapt to a range of stress changes. Thus, HA ceramics development from dense to porous has important significance bionic. The surface structure of the stent, pore structure, pore size and porosity etc. affect their biological functional of bone scaffold material. The pellets prepared by stacking scaffold has the following characteristics:penetration resistance, high porosity, macro-pore structure of uniform. As a single pellet, it can be carried out drug containing growth factors, etc., in order to improve the biological activity of the accumulation of the stent. To further investigate the micro-structural support scaffold induction of ectopic bone, we designed ceramic pellets prepared with extensive microscopic pore structure, and accumulate the pellets into the scaffold to study the impact of systematic research on the microstructure of the biological function of the stent, and exploring the technical means to control the accumulation of arbitrary morphology of the stent as well. We take use of extensive stents microscopic pore structure as a drug carrier to promote bone regeneration drugs improve bone tissue repair capacity.In this study, we the first take study of the sol-gel method hydroxyapatite (HA) pellets, and it has a wealth of microscopic pore structure and surface morphology of the complex method using pore-forming agent. Subsequently piled into the scaffold, study the effects of this kind of preparation stent accumulation of all aspects of its performance. Meanwhile, we studied for the preparation of pellets scaffold depth application. By in vitro cells, bio mimetic mineralization experiments we investigate the influence of microstructure on its stand of biological functions, and the drug release experiment, and achieved satisfactory results. The main conclusions of this study are as follows:1. Sol-gel method can be successfully prepared form stable spherulitic hydro xyapatite ceramic particles. Two porogen is used as a combination to build rich microstructure spheroids. SEM observation the rich spherules internal microstructure and pellets have a higher porosity.2. We using adhesive manner pellets assembled into ceramic pellets stacked scaffold which has high mechanical properties. We also achieved high porosity piled stent with high porosity pellets. We achieved composite structural support with bracket scaffold wrapped pore scaffold compare with the natural thinning of dense bone structure further improve the porosity of the scaffold, while maintaining a high mechanical properties.3. We investigate the biological activity of the porous structure of the scaffold through in vitro experiments and biomimetic. It resulted that the HA pellet holder with respect to the porous structure of the scaffold has a small hole the better biological activity. Rich pores and wrinkles favor osteoblast adhesion, spreading and proliferation activity. It also provides three-dimensional growth environment and in favor of early calcium phosphate salt deposition.4. HA pellets found in the porous structure of the scaffold has a better drug loading capacity in order to the accumulation of drug adsorption scaffolds. The effect of drug delivery can be achieved by coating the drug loaded scaffolds with chitosan concentration of 1% or more.5. Spheres stacked scaffolds with microscopic extensive macro pore structure has excellent mechanical properties, biological properties and drug release capabilities. It provides a new way to seek the source of bone prosthesis when a big slice of bone defects.