Preparation Of Chitosan Microsphere Incorporating BFGF And Its Effect On Schwann Cells

Objective: To study the preparation method of bFGF Chitosan microspheres and to investigate the bioactivities of bFGF, which were released from the bFGF microspheres, on the cultured schwann cells.Methods:bFGF was microcapsulated with the emulsification crosslinking method using Chitosan as coating material. Its morphology, particle size distribution, drug loading, embedding rate and in vitro release property were studied.The cultured schwann cells were grouped according to the different ingredients being added to the culture medium:bFGF group, bFGF- Chitosan group. Then the number, the viability and the cell cycle of schwann cells were measured.Results:the surface of the bFGF- Chitosan microspheres were rounder, smooth and no apparent porosity distribution uniformity; the average particle size of microspheres were35.335um; the drug-loading and drug-embedding rate of microspheres were7.57mg/g,95.14%; the release property of microspheresin vitro was good and the overall release rate was 82.04%in24 days. The in vitro cellular study showed:1,2 days after plate culture, the cell number and cell viability of bFGF group was much better than that of bFGF- Chitosan group (p<0.005); 3,4 days after plate culture, the cell number and cellviability of bFGF group and bFGF-Chitosan group were not different statistically (p>0.005); 6,8 days after plate culture, thecell number and cell viability of bFGF-Chitosan group was much better than that of bFGF group (p<0.005). Through the flow cytometry examination:2 days after plate culture, the G2/M+S percentage of bFGF group was higher than that of bFGF- Chitosan group (p<0.005); 4,8 days after plate culture, the G2/M+S percentage of bFGF-PLGA group was higher than that of bFGF group (p<0.005)Conclusion:it is practical to prepare the bFGF- Chitosan microspheres with the emulsification crosslinking method.the surface of the bFGF- Chitosan microspheres were rounder, smooth and no apparent porosity distribution uniformity;bFGF- Chitosan microspheres can preserve the bioactivities of bFGF effectively and promotes the proliferation of schwann cells in a long period because of the controlled release of bFGF from microspheres.