Mineralization of chitosan rods with concentric layered structure induced by chitosan hydrogel.
Ca ions and P ions absorbed by chitosan hydrogel with a molar ratio of 1.19 were converted into carbonated apatite under ambient condition, by alternate soaking in combination with alkali treatment within a few hours. The alkali treatment helped to convert amorphous calcium phosphate in chitosan hydrogel into carbonated apatite. The bending strength of mineralized chitosan with a concentric layered structure varied from 62.7 MPa to 92.5 MPa, which was 45.8-67.5% as strong as that of rabbit femur. During the process of alternate soaking and alkali treatment, chitosan hydrogel not only provided a medium for the carbonated apatite coating reaction which helped to form the concentric layered structure due to the Liesegang rings phenomenon, but also induced absorption of Ca and P ions in the hydrogel framework via chelation or electrostatic interaction rather than the diffusion model originated from the concentration gradient.
Li
Baoqiang
B
Institute for Advanced Ceramics, Harbin Institute of Technology, Harbin 150001, People's Republic of China. libq@hit.edu.cn
Wang
Yongliang
Y
Jia
Dechang
D
Zhou
Yu
Y
Cai
Wei
W
D001031:Apatites / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D004548:Elasticity; D020100:Hydrogels / Q000737:chemistry*; D008422:Materials Testing; D008903:Minerals / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties; D013718:Tensile Strength
D001031:Apatites; D001672:Biocompatible Materials; D002130:Calcium Phosphates; D020100:Hydrogels; D008903:Minerals; D048271:Chitosan; C020243:calcium phosphate