Preparation and characterization of fibrous hydroxyapatite/chitosan nanocomposites with high hydroxyapatite dosage

摘要

In this paper the hydroxyapatite fibers reinforced chitosan nanocomposites with high hydroxyapatite dosage (70~90 wt%) were synthesized by in-situ hybridization. The semi-permeable membrane was used to control the process of hybridization and morphology of hydroxyapatite. The compositional and morphological properties of nanocomposites were investigated by FTIR spectroscopy, X-ray diffraction, and transmission electron microscopy. The results showed that the hydroxyapatite were carbonated nanometer crystalline fibers with high aspect ratio (about 25) and dispersed uniformly in the nanocomposites. The high-resolution image indicated that the growth of nano-hydroxyapatite crystallites in the chitosan matrix preferred in the c-axis. The mechanical properties of these nanocomposites were enhanced dramatically and the compressive strength increases almost to 170MPa when the hydroxyapatite content is 70 wt%. The in vitro tests indicated that the composites have high bioactivity and degradation. These properties illustrated the potential application of this kind of nanocomposites for bone tissue engineering.