Preparation and characterization of bionic bone structure chitosan/hydroxyapatite scaffold for bone tissue engineering

Abstract

Three-dimensional oriented chitosan (CS)/hydroxyapatite (HA) scaffolds were prepared via in situ precipitation method in this research. Scanning electron microscopy (SEM) images indicated that the scaffolds with acicular nano-HA had the spoke-like, multilayer and porous structure. The SEM of osteoblasts which were polygonal or spindle-shaped on the composite scaffolds after seven-day cell culture showed that the cells grew, adhered, and spread well. The results of X-ray powder diffractometer and Fourier transform infrared spectrometer showed that the mineral particles deposited in the scaffold had phase structure similar to natural bone and confirmed that particles were exactly HA. In vitro biocompatibility evaluation indicated the composite scaffolds showed a higher degree of proliferation of MC3T3-E1 cell compared with the pure CS scaffolds and the CS/HA10 scaffold was the highest one. The CS/HA scaffold also had a higher ratio of adhesion and alkaline phosphate activity value of osteoblasts compared with the pure CS scaffold, and the ratio increased with the increase of HA content. The ALP activity value of composite scaffolds was at least six times of the pure CS scaffolds. The results suggested that the composite scaffolds possessed good biocompatibility. The compressive strength of CS/HA15 increased by 33.07% compared with the pure CS scaffold. This novel porous scaffold with three-dimensional oriented structure might have a potential application in bone tissue engineering.

Keywords:

• chitosan
• hydroxyapatite
• three-dimensional oriented scaffold
• bone tissue engineering
• in situ precipitation

Funding

This work was partially funded by National Natural Science Foundation of China [Grant Nos. 21104067 and 21274127], the Key Basic Research Development Plan (Project 973) of China [Grant Nos. 2011CB606203 and 2009CB930104], Grand Science and Technology Special Project of Zhejiang Province [Grant No. 2008C11087], and Fundamental Research Funds for the Central 20 Universities (2013QNA4048).