6. 透明质酸涂层PLLA-明胶三维纳米纤维支架用于软骨再生

6. 透明质酸涂层PLLA-明胶三维纳米纤维支架用于软骨再生

      利用静电纺和冷冻干燥相结合的技术可制备出纳米纤维三维多孔支架，三维支架的制备流程可概括为：   

    （1）静电纺丝制备明胶与PLA复合的纳米纤维膜；   

    （2）将纤维膜剪碎，置于叔丁醇中利用高速匀浆机将纤维分散均匀；   

    （3）冷冻干燥成型;

    （4）交联三维支架；对明胶/PLA三维支架进行修饰，将透明质酸（HA）通过EDC/NHS接枝于三维支架纤维的表面。制备出的纳米纤维三维支架在湿态下具有海绵一样的弹性，三维支架还具有形状记忆功能，此支架被成功用于兔髌骨软骨缺损的修复。制造新西兰大白兔关节软骨缺损，将HA修饰支架和未修饰支架植入软骨缺损处，动物实验结果表明，经HA修饰的三维支架可以明显促进大白兔关节软骨缺损的修复。

6. Hyaluronic acid coated PLLA-gelatin three-dimensional nanofiber scaffold for cartilage regeneration

The nanofiber three-dimensional porous scaffold can be prepared by the combination of electrospinning and freeze-drying. The preparation process of the three-dimensional scaffold can be summarized as follows:

(1) electrospinning to prepare gelatin-PLA composite nanofiber membrane;

(2) fiber membrane were chopped, placed in t-butanol using a high-speed homogenizer to disperse the fibers evenly;

(3) freeze-dried;

(4) cross-linked three-dimensional scaffold; modified gelatin/PLA three-dimensional scaffold by hyaluronic acid (HA) grafted onto the surface of the three-dimensional scaffold fiber with EDC/NHS. The prepared nanofiber three-dimensional scaffold has sponge-like elasticity in a wet state, and the three-dimensional scaffold also has a shape memory function. The scaffold is successfully used for repairing a rabbit tibial cartilage defect. The articular cartilage defects of New Zealand white rabbits were made, and HA modified scaffolds and unmodified scaffolds were implanted into the cartilage defects. The results of animal experiments showed that HA-modified three-dimensional scaffolds could significantly promote the repair of articular cartilage defects in white rabbits.