Study On Surface Modification Porous NHA/Mg Composite Materials With CS And PLGA

Disease causes maxillofacial bone defects, such as trauma, tumor, chronicinflammation. Bone tissue engineering is the most forward-looking approach to solvethis problem. Scaffold materials as one of the essential factors of tissue engineering,not only to have good biocompatibility, but also have a pore structure, to providevalue-added space for cell differentiation and vascular ingrowth. Therefore, porousscaffold materials tend to be the research focus. Magnesium and Mg-based porematerials have good biocompatibility and degradability, and good osteoconductive forbone, so as the bone regeneration material has great potential for jaw bone defectreconstruction. Because of fast decomposition in vivo, magnesium supports poorretention effect as a implant. Therefore, this article takes magnesium/nanohydroxyapatite porous composite material as the research object, using Chitosan(Chitosan, CS), poly lactic acid/glycolic acid copolymer (PLGA) on the surfacemodification treatment, and compound a new type of biodegradable composites toprovide scientific basis for application of magnesium-based materials in clinicalapplication.This experiment prepared nHA/Mg composite material by powder metallurgymethod with magnesium and nHA as raw materials, preparation chitosan and PLGAcoating by immersion method in nHA/Mg composite surface, analyze the surface andmorphological structure and pH of SBF with advanced test method. Ammoniumbicarbonate and nHA content on the composite material is discussed the change ofporosity and mechanical properties. Obtained the ideal tissue engineering scaffoldmaterial.The nHA/Mg composites were synthesized by simple and accurate powdermetallurgy with ammonium bicarbonate as pore-forming agent. nHA/Mg compositematerial has ideal pore structure, porosity of50%on average, about50~120microns;content nHA for10wt%,30wt%, the compound material mechanics performance isbetter. The surface of two kinds of membrane material By immersion method is smoothand without cracks and holes. Weight of chitosan coating is directly proportional tothe immersion time; and PLGA coating changes little after48h, nHA/Mg compositematerial to achieve maximum penetration PLGA solution at48h. Simulated body fluidcorrosion experiments show that both kinds of coating can effectively reduce thespeed of the degradation of composites, to extend the time of its remaining incorrosive liquid, reduce the pH value of material corrosion liquid, but the pH value ofPLGA coating group is lower, more close to neutral, the effect to improve thebiocompatibility of composite material is stronger.