Biomaterials incorporating releasable growth factor

将碱性成纤维细胞生长因子（bFGF）通过多聚络合浸渍到酸性明胶交联制备的等电点为4.9的可生物降解水凝胶中。释放实验表明，在体外非降解条件下，明胶水凝胶不释放bFGF。水凝胶在小鼠背部皮下植入后随时间降解，体内降解时间随水凝胶含水量的不同而不同。含有bFGF的明胶水凝胶能强烈诱导植入部位周围的新生血管形成，而皮下注射溶液形式的bFGF并没有增加组织血红蛋白的数量和组织的湿重。低含水量的bfgf浸渍明胶水凝胶维持血管化效果的时间较长。由此得出结论，在明胶水凝胶中，由于其体内降解而释放出bFGF，因此比未浸没在水凝胶中的游离bFGF更有效地诱导新生血管形成。

Basic fibroblast growth factor (bFGF) was impregnated through polyin complexation into biodegradable hydrogels prepared by crosslinking of acidic gelatin with the isoelectric point of 4.9. Release experiments demonstrated not to release bFGF from the gelatin hydrogel under the in vitro non-degradation conditions. The hydrogels were degraded with time following their subcutaneous implantation on the mouse back and the period of in vivo degradation varied depending on the water content of hydrogels. The gelatin hydrogels containing bFGF strongly induced neovascularization around the implantation site, whereas subcutaneous injection of bFGF in the solution form did not increase the amount of tissue hemoglobin and the wet weight of tissue. The bFGF-impregnated gelatin hydrogel of lower water content retained the vascularization effect for a longer period. It was concluded that bFGF was released from gelatin hydrogel as a result of their in vivo degradation, leading to more efficient induction of neovascularization than free bFGF without impregnation in the hydrogel.