透明质酸改性PHBV组织工程纳米纤维支架的研究

组织工程支架材料表面性质对细胞的黏附起着重要作用,进而影响细胞的增殖、分化等一系列生长过程.本研究采用天然生物大分子透明质酸(hyaluronic acid,HA)对聚(3-羟基丁酸酯-co-3-羟基戊酸酯)(Poly(3-hydroxybutyrate-co-3-hydroxyvalerate),PHBV)进行表面修饰以提高材料的表面生物活性.首先通过静电纺丝法制备PHBV纳米纤维支架,利用1,6-己二胺胺解在PHBV表面引入自由胺基,并以此为反应活性位点在水溶性的碳化二亚胺/N-羟基琥珀酰亚胺缩合剂体系中将透明质酸固定接枝在PHBV表面.SEM结果表明,静电纺丝制备的PHBV纳米纤维支架表面平滑程度高,纤维直径分布较均匀,且没有串珠;FTIR证明1,6-己二胺改性及透明质酸接枝改性PHBV纳米纤维支架材料均成功实现;茚三酮法表明PHBV表面胺基密度随胺解时间增加而增大,在胺解约50min时达到最大值;水接触角法表明固定接枝透明质酸后,表面亲水性明显改善;细胞实验表明透明质酸改性的PHBV纳米纤维支架可显著促进软骨细胞的体外增殖.综上所述,透明质酸改性的PHBV纳米纤维支架可望应用于软骨组织工程领域.

Surface Modification of PHBV Tissue Engineering NanofibrousScaffolds with Hyaluronic Acid

Surface properties of tissue engineering scaffold play important roles in cell adhesion and other biological processes such as cell proliferation,differentiation. In this study,the surface modification of Poly (3 hydroxybutyrate co 3 hydroxyvalerate) (PHBV) was performed in order to improve the biological activity of material surface. PHBV nanofibrous scaffold was firstly made by electrostatic spinning method,introducing free amino groups in the PHBV surface through 1,6 hexanediamine,which provided reaction sites for the further immobilization of hyaluronic acid (HA) macromolecules. The morphology observed by SEM showed that PHBV nanofibrous scaffolds prepared by electrostatic spinning method have smooth surfaces without obvious beads defects and their fiber diameters uniformly distribute. FTIR analysis proved that 1,6 hexanediamine and hyaluronic acid modified PHBV fibrous scaffolds were successfully achieved. The ninhydrin determination results showed that the surface amine group density,which increased with the extending of aminolysis time,reached its maximum at 50 minutes. Furthermore,there is no significant difference on the morphology of the scaffolds before and after modification by statistic comparison. The water contact angle significantly decreased after the immobilization of hyaluronic acid,indicating that the hydrophilicity was obviously improved after surface modification with the hydrophilic natural biological macromolecules. The Alamar Blue assay manifested that hyaluronic acid modified PHBV nanofibrous scaffolds could significantly promote the chondrocytes proliferation in vitro. Therefore,the hyaluronic acid modified PHBV nanofibrous scaffolds are potential for application in cartilage tissue engineering.