Chemically modified light-curable chitosans with enhanced potential for bone tissue repair.

Abstract

Light curable polymers are showing great potential in overcoming some of the current obstacles in bone repair. With stereolithography, they can be fabricated into scaffolds with desired topography for repairing bone defects in irregular shapes. In this study, we developed a series of light curable chitosans, which have photocurability and good solubility in organic solvent. Through adjusting the feeding ratio of the raw components, the content of photocurable groups in the backbone of chitosan can be controlled. The light curable chitosans were characterized through FTIR-ATR and (1)H NMR, which also confirmed their controllable photocurability. NIH 3T3 fibroblasts were co-cultured with the photocured samples for 7 days and the results indicated that these photocured chitosans are cyto-compatible. Scaffolds with interconnected pores, fabricated using salt leaching and photocuring and seeded with fetal bovine osteoblasts, were implanted subcutaneously in the backs of athymic rat. Histological study on the implants at 6 weeks showed that the photocured chitosans have good osteoconductivity. The results indicated the light curable chitosans have good biocompatibility and osteoconductivity.