Poly(lactic acid) scaffold fabricated by gelatin particle leaching has good biocompatibility for chondrogenesis

Three-dimensional poly(L-lactic acid) (PLLA) scaffolds with high porosity and an average pore size of 280-450 microm were fabricated using gelatin particles as porogen. The particles were bonded together by incubation in saturated water vapor at 70 degrees C for 3.5 h. After casting the PLLA/1,4-dioxane solution, freeze-drying and porogen leaching with 70 degrees C water, a porous scaffold with well-interconnected pores and some nano-fibers was obtained. The biological performance of the scaffold was evaluated by in vitro chondrocyte culture and in vivo implantation. In comparison with the control scaffold fabricated with NaCl particles as porogen under the same conditions, the experimental scaffold had better biological performance because the gelatin molecules were stably entrapped onto the pore surfaces. A larger number of cells in the experimental scaffold were observed by confocal laser scanning microscopy after the viable cells had been stained with fluorescein diacetate. The chondrocytes showed more spreading morphology. Higher cytoviability and secretion of glycosaminoglycan (GAG) were also determined in the experimental scaffold. After implantation of the chondrocytes/PLLA scaffold construct to the subcutaneous dorsum of nude mice for 30-120 days, cartilage-like specimens were harvested. Histological examination showed that the regenerated cartilages had a large quantity of collagen and GAG.