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To obtain a single material is difficult to meet the requirements of bone tissue engineering scaffold, thus the different nature of the material composite scaffolds become research hotspot of biological materials with new performance hybrid. The hydroxy-apatite (hydroxyapatite, HA) having a natural bone inorganic minerals similar chemical composition, but also has a high mechanical strength and good biological activity, but it brittle and very low rate of biodegradation in a way has limited its application in bone tissue engineering. Chitosan (chitosan, CS) are an important class of overbased natural polysaccharide, having a good biological degradability, bio-renewable, non-toxic, biocompatible and biological function, and therefore in the field of biomedical broad application prospects. However chitosan does not have biological activity, and lower mechanical strength, making it difficult for complex parts of bone repair and reconstruction. By chitosan / hydroxyapatite composite can overcome the deficiencies of each of the two single-component materials. While chitosan / hydroxyapatite composite has been great progress, but until now, due to the two-phase interaction of organic and inorganic lack of a variety of reasons, in this area of ??research is still rarely able to apply in clinical. In order to get a better overall performance, many researchers add into a biopolymer material as a reinforcing phase, such as adding phosphorylated chitosan (the phosphorylated chitosan PCS). The chemical modification of the material is one of the main methods of it with new properties, the presence of an amino group and a hydroxyl group so that the chitosan has a great advantage in the reforming reaction, in recent years, a variety of chemical methods have been applied chitosan the preparation of the sugar-phosphate derivatives, chitosan phosphate having the role of adsorbed metal ions and biocompatibility. If hydroxyapatite, chitosan and phosphorylated chitosan advantage of the three-phase material, promising to develop a new type of bone tissue engineering using bio-composite materials. In this paper, chitosan and phosphate chemical reagents prepared by the reaction of the phosphorylated chitosan and quality than different PCS / CS / HA composite powder prepared by coprecipitation, composite molding in order to The rod used for compression strength test. Phosphorylated chitosan show that the phosphorylation modified chitosan was successful. In addition, we also study the impact of the aging process on the performance of hydroxyapatite, the results show that aging can improve the stability of the crystal and crystallography precipitation. Compression strength test, carried out on the composite rods When PCS / CS / HA composites three mass ratio of 30/30/40, the compression strength of 70.25MPa, is the maximum value of the article, in bone tissue engineering having great application potential. This article further research a mass ratio of 30/30/40 of the composite material sheet in the simulated body fluid (simulated body fluid, SBF) in the biological activity, the results showed that the adhesion and proliferation of the microporous structure of the surface of the sheet on osteoblasts promoting effect, with citric acid aqueous solution containing citrate as excipients molded composite material has a better biological activity. Composite Rods remains that 64% of the compression strength after 20 days immersion in SBF. At the same time on the the biomineralization mechanism and biological degradation mechanism was discussed. In addition, prepared to meet the basic compression strength requirements of bone tissue engineering scaffolds.
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