Department of Chemical and Materials Engineering, National Central University, Taiwan; Centre for Biomedical Cell Engineering, National Central University, Taiwan.
Department of Chemical and Materials Engineering, National Central University, Taiwan.
Int J Biol Macromol. 2019 Jan;121:1337-1345. doi: 10.1016/j.ijbiomac.2018.09.043. Epub 2018 Sep 7.
Alginate and polycaprolactone (PCL) were coelectrospun as composite nanofibers for in situ transfection, in which anionic alginate fibers were used to adsorb polyethyleneimine (PEI)/DNA polyplexes and biocompatible PCL fibers were applied to promote cell adhesion. To improve gene immobilization, direct-current electric field (DCEF) was applied to guide cationic polyplexes toward nanofibers on cathode. Fluorescent labeling experiments suggested that the applied DCEF not only accelerated but also increased the saturation levels of gene immobilization. Interestingly, these DCEF also increased the degradation of nanofibers. The water contact angle and Fourier-transform infrared spectrometry results indicated that the degraded component was mainly alginate. It suggested that the DCEF treatment may cause the electrophoresis of calcium ions to destabilize alginates fibers, and thus the degradation rates increased with the applied voltages. This alginate degradation increased the ratio of PCL in composite fibers, so the cell adhesion, viability, and proliferation were improved. Finally, these DCEF-treated fibers were used for substrate-mediated gene delivery. The transfection efficiency highly increased with DCEF when the voltages were lower than 1.5 V. This dynamic scaffold system not only provided a suitable microenvironment for cell ingrowth, but also improved gene immobilization and transfection, and thus promised its therapeutic effect for tissue regeneration.
海藻酸钠和聚己内酯（PCL）被共纺成复合纳米纤维用于原位转染，其中阴离子海藻酸钠纤维用于吸附聚乙烯亚胺（PEI）/DNA 聚集体，生物相容性的 PCL 纤维用于促进细胞黏附。为了提高基因固定化效率，施加直流电场（DCEF）以引导阳离子聚集体向阴极的纳米纤维移动。荧光标记实验表明，施加的 DCEF 不仅加速了，而且提高了基因固定化的饱和度水平。有趣的是，这些 DCEF 还增加了纳米纤维的降解。水接触角和傅里叶变换红外光谱结果表明，降解的主要成分是海藻酸钠。这表明 DCEF 处理可能导致钙离子电泳使海藻酸盐纤维不稳定，因此降解速率随施加电压的增加而增加。这种海藻酸钠的降解增加了复合纤维中 PCL 的比例，从而提高了细胞黏附、活力和增殖。最后，这些经过 DCEF 处理的纤维被用于基底介导的基因传递。当电压低于 1.5V 时，施加 DCEF 可以显著提高转染效率。这种动态支架系统不仅为细胞向内生长提供了合适的微环境，而且提高了基因固定化和转染效率，从而有望为组织再生提供治疗效果。
