| In recent years, along with the biomedical material domain's development, there are active studies in the filed of biomaterials to simulate nature bone. Hydroxyapatite (HA) is believed to be the best material for bone structure, specially the Nano-HA because of its better biocompatibility over traditional one. The HA in nature bone tissue is kind of nano-HAP with low calcium phosphorus ratio. The composite scaffolds which simulate both the chemical composition and the nanometer size of the nature bone will become the ideal scaffold for bone tissue engineering. It will have more advantages in vivo cell's adheres, the growth and the differentiation.Hydroxyapatite (Ca10(PO4)6(OH)2,HA) was widely used for bone tissue engineering due to its good bioactivity and biocompatibility. However, there are some limitations in their usage because their brittleness makes them hard to process. In order to overcome the hydroxyapatite's low bending strength, many kinds of polymer are adding to prepare the compound materials which could improve the original mechanical properties.In this thesis, the nano-hydroxyapatite, ?-Tricalciumphosphate, the collogen and the chitosan are chosen as materials. The composite scaffolds with nine different ratios of nano-HA and ?-TCP content were fabricated by using lyophilization method. Their microscopy, physical and chemical properties were investigated by using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transformed infrared (FTIR) spectroscopy. At the 1, 3, 5, 7, 14, 21 and 28 days, MTT test was applied to quantitatively assess the number of viable cells attached and grown on the scaffolds. And the result showed that the amount of cells on the scaffold containing 20-30% by mass of nano-HA was significantly higher than other samples. And the results revealed that nano-HA/TCP/CS composite scaffolds have good surface morphology and the nano-HA particles were homogenously dispersed in the chitosan matrix. The porosity of the scaffold is up to 90%.
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