Carbon nanotubes (CNTs)/hydroxyapatite (HA) nanocomposites have been successfully fabricated by a novel method for the biomedical applications, which is in situ growing CNTs in HA matrix in a chemical vapor deposition (CVD) system. The results show that it is feasible to in situ grow CNTs in HA matrix by CVD for the fabrication of CNTs/HA nanocomposites. Multi-walled CNTs with 50-80 nm in diameter have been grown in situ from HA matrix with the pretreatment of sintering at 1473K in air. The nanocomposites are composed with carbon crystals in CNTs form, HA crystallites and calcium phosphate crystallites, one of most important CaP bioceramics. And the CNTs content is about 1% proportion by weight among the composites in our experiments, which can enhance the HA mechanical properties and the CNTs content does not affect the HA performances. These CNTs/HA nanocomposites have the potential application in the biomedical fields.

The morphological differences of chitosan (CS) in the hydroxyapatite (HA)/CS nanocomposites were investigated in detailed, which were prepared via in situ hydrothermal precipitation. The results show that the obtained nanocomposites have excellent crystallinity and the crystal has excellent ordered structure, which is important to the composites performances in the biomedical application. Moreover, the CS arrangement and crystallinity in the composites greatly depend on the hydrothermal temperature and the pH value of precipitating agent. The temperature ranging from 373 to 413K and pH value of precipitating agent ranging from 12 to 14 were favorable to the crystallization and oriented growth of CS molecules in the composites. The CS crystals with better arrangement are assembled in the order of layer-by-layer in these composites.

A novel two-step foaming process has been developed to prepare the porous titanium implant. By using H2O2 and stearic acid as foaming reagent ordinally, a foamed structure with an open, interconnected pore morphology was obtained. The mechanical property was determined by compressive test. In vitro study was conducted to evaluate the ability of the porous titanium to support the growth and differentiation of Human osteosarcoma cell line MG63. The results show that the porous titanium has better interconnection compared to that obtained by traditional slurry foaming and its compressive strength and Young’s modulus were approximate 23.6 MPa and 2.1 GPa, respectively. Cell culture experiment results indicate that the porous titanium has good biocompatibility and acid-alkali treatment facilitates the adherence and proliferation of cells.

In the present work, technique of plasma polymerization was used to generate amido (- NH2) and carboxyl (-COOH) on titanium surface for immobilizing bovine serum albumin (BSA). After plasma polymerization of allylamine and crylic acid, the contact angle with respect to double distilled water significantly increased. Surface components were detected by X-ray photoelectron spectroscopy and Fourier transform infrared reflection-absorption spectroscopy. The results showed that BSA was successfully immobilized on the titanium surface and the amounts of BSA on specimens were relied on the properties of thin film deposited through plasma polymerization, which was corresponding to the ultraviolet spectrophotometer result.

Porous hydroxyapatite (HA) ceramic scaffolds are extensively used to induct the tissue growth for bone repair and replacement, and serve functions to support the adhesion, transfer, proliferation and differentiation of cells. Highly porous structure is always expected for its positive effect on the bone regeneration in vivo, nevertheless high porosity always accompanies a decrease in strength of the HA ceramic scaffolds. Therefore, it is significant to improve the strength of the HA ceramic scaffolds with highly interconnected porosity so that they are more suitable in clinic applications. The aim of this study is to investigate the effect of starting materials on mechanical property of final scaffold in order to optimize the preparation process. In this work, three starting HA particles with different morphologies are used to prepare highly porous HA ceramic scaffolds by the polymer impregnation approach in the same preparation process. The phase composition, microstructure and mechanical properties of the sintered porous HA scaffolds are investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and compressive test. The experimental results show that the particle morphologies have influence on the slurry viscosity and further affect the coating amount on the sponge. The porous HA ceramics fabricated by spherical HA particle hold the highest compressive strength than the other two HA scaffolds for better sintering property. It is an effectively method to improve the mechanical property of porous HA ceramic scaffolds by optimizing the starting particle morphology.