同轴静电纺丝法制备血管内皮生长因子纳米纤维缓释载体

Preparation of coaxial electrospinning nanofibers for vascular endothelial growth factor delivery

目的应用同轴静电纺丝的方法制备以聚己内酯（PCL）为壳层，血管内皮生长因子（VEGF）和牛血清蛋白（BSA）为芯的纳米纤维缓释载体，观察其体外缓释VEGF的特性，并检测释放VEGF的活性。方法观察15—18kV电压下制备出来的VEGF纳米纤维缓释载体的形貌结构特征，分别在第1、3、7、15、30天检测BSA和VEGF的释放量分别为BSA／PCL（17％、34％、38％、45％、56％），BSA／PCL．聚乙二醇（PEG）（30％、45％、80％、89％、92％），VEGF（5％、10％、20％、60％、90％），绘制时间．累积释放量曲线（％），检测释放VEGF的活性，并与新鲜的VEGF组和无VEGF组作为平行对照。结果15、16、17、18kV制备出来的同轴静电纺丝直径为分别为（282．00±43．57）、（199．13±32．87）、（182．00±27．74）、（159．00±36．33）nm。VEGF在30d内逐渐释放，累积释放量98％，释放出来YEGF的生物学活性与新鲜的VEGF之间差异无统计学意义（P〉0．05），与无VEGF之间差异有统计学意义（P〈0．05）。结论运用同轴静电纺丝技术成功制备了以PCL为壳层，VEGF和BSA为芯的纳米纤维缓释载体，通过调整电压可以控制纳米纤维的直径，该载体还能够保持VEGF的生物学活性并持续释放，同时可以通过加入PEG来调节其释放量。

Objective To construct coaxial electrospinning nanofibers with poly （ε-caprolactone） （PCL） as the shell and BSA and vascular endothelial growth factor （VEGF） as the core, expore its ability for VEGF delivery in vitro, and examine the biological activity of VEGF released. Methods The morphology of VEGF coaxial electrospinning nanofibers was observed at the voltage from 15-18 kV. At 1st, 3rd, 7th, 15th, and 30th day, bovine serum albumin （BSA）/PCL was 17%, 34%, 38%, 45% and 56%, BSA/PCL-polyethyleneglycol （PEG） was 30%, 45% , 80% , 89% and 92% , and VEGF release was 5% , 10% , 20%, 60% , 90% , respectively. The curve of time-cumulative release percentage was drawn. At last, the biological activity of VEGF released was tested. Results The diameters of nanofibers at the voltage of 15, 16, 17 and 18 kV were （282.00 ±43.57）, （199. 13 ±32.87）, （182.00 ±27.74）, （ 159. 00 ± 36. 33 ） nm respectively. The VEGF was released gradually within 30 days, and the cumulative release percentage was almost 98%. The biological activity of the released VEGF has no significant difference from the fresh VEGF （ P 〉 0. 05 ）, but significant difference from no-VEGF group （ P 〈 0. 05 ）. Conclusion We construct the VEGF coaxial electrospinning nanofibers with PCL as the shell and BSA and VEGF as the core, and can change the diameter of nanofibers by adjusting the voltage. The nanofobers can retain biological activity of VEGF and release VEGF gradually, and can also adjust the releasing by adding PEG.