Synergistic effect of functionalized poly(l-lactide) with surface-modified MgO and chitin whiskers on osteogenesis in vivo and in vitro.

Favorable cytocompatibility and osteogenesis potential are critical for the development of a bone repair material. In this study, two types of surface-modified whiskers, grafted magnesia and chitin (g-MgO and g-CHN) whiskers, were synthesized and introduced into a poly(l-lactide) (PLLA) matrix singly or together to prepare PLLA/g-MgO/g-CHN composite films and bone nails via injection molding. On the account of the synergetic contribution of g-MgO and g-CHN whiskers, the enhanced cell adhesion, spreading, proliferation of mouse embryo osteoblast precursor (MC3T3-E1) cells, as well as the alteration of cell-cycle and inhibition of cell apoptosis, were observed on PLLA/g-MgO/g-CHN film as compared to pure PLLA, PLLA/g-MgO and PLLA/g-CHN films.

Synergistic Effect of Surface-Modified MgO and Chitin Whiskers on the Hydrolytic Degradation Behavior of Injection Molding Poly(l-lactic acid).

To regulate the degradation behavior of poly(l-lactic acid) (PLLA) for its use as a bone internal fixation material, surface grafted magnesium oxide and chitin whiskers (-MgOs and -CHNs) were added to PLLA in combination or separately via injection molding in this study. The as-prepared binary or ternary composites were degraded in vitro in PBS solution with a pH value of 7.4 at 37.