Preparation And Characterization Of Hydroxyapatite Nano-biomaterials

With the development of science and technology, new materials are used widely in all areas of the society. The application of biological material has got unprecedented attentions. Hydroxyapatite (HA) has many medical functions and good bioactivity and biocompatibility. In order to meet the clinical demand, a novel method for the preparation of HA nano-biomaterials was developed in this article. The composite system of polysaccharide and HA which all possessed good bioactivity and biocompatibility was studied. HA nano-biomaterials were prepared by biomimetic method and were also characterized. Then the factors that affected the preparation of nano-biomaterials were discussed. The main contents and results of the work are as follows:1. Water-soluble carboxymethyl glucosan (CMG) was prepared and used to induce the growth of HA by the reaction with Ca²⁺. Then CMG/HA nano-composite particles were synthesized. The particles were characterized by FT-IR, TEM, XRD and Zeta potential etc. The results showed that the HA nano-particles were wrapped by CMG, the CMG/HA nano-composites were spherical and stable. The diameters of HA core CMG shell (HA @CMG) were about 100nm and 120nm, respectively. The mechanism of HA @CMG nano-composite particles was also disscussed.2. carboxymethyl chitosan (CMC) was used as template for the synthesis of CMC/hydroxyapatite (HA) nano-composite particles. The results showed that the CMC/HA nano-composite particles are stable. The shape of particles is diverse, such as clava, cube, sphere and fractal. The influence of dispersant and cross-linking on CMC/HA nano-composite particles was studied. The results suggested that the CMC/HA nano-composite particles was difficult to gather.3. Fe₃O₄ nano-particles with the average diameter of 25nm were prepared by sedimentation-oxygenalion method. Nano-composite particles containing CMC/HA/Fe₃O₄ were prepared. The analysis of the FT-IR indicated the nano-composite particles exactly contained the three components as expectation. The XRD analysis also demonstrated the presence of HA and Fe₃O₄, indicating the combination of the three components was possibly due to the hydrogen bond or coordination.4. Different parts of pig bones (hard bones, articular bones and soft bones) were selected to prepare collagen (Col) and HA nano-particles by acid-dissolution method. Comparative experiments were done to analyze the difference between the preparation of Col and HA using pig bones from different parts, and to explore the probability of preparing Col and HA from the same bone. The characterizations of UV-Vis, FT-IR and XRD showed articular bones and soft bones were suited to distill the Col and hard bones were suitable for the preparation of HA. The acid-dissolution method was successfully used to distill Col, which was not suitable for the preparation of HA. But HA with the average diameter of 40nm was prepared by the calcination of hard bones.