title: Mineralization of chitosan rods with concentric layered structure induced by chitosan hydrogel.
abstract: 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.
authors.affiliation: Institute for Advanced Ceramics, Harbin Institute of Technology, Harbin 150001, People's Republic of China. libq@hit.edu.cn
authors.forename: Baoqiang
authors.initials: B
authors.lastname: Li
authors.forename: Yongliang
authors.initials: Y
authors.lastname: Wang
authors.forename: Dechang
authors.initials: D
authors.lastname: Jia
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhou
authors.forename: Wei
authors.initials: W
authors.lastname: Cai
mesh_terms: 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
chemical_list: D001031:Apatites; D001672:Biocompatible Materials; D002130:Calcium Phosphates; D020100:Hydrogels; D008903:Minerals; D048271:Chitosan; C020243:calcium phosphate