慢性傷口因癒合緩慢，造成感染風險增加，因此需開發多功能的傷口敷料以促進組織再生並達到抗菌的效果。本研究將褐藻酸鈉(Alg)與載入增加親水性的介孔二氧化矽奈米粒子(MSN)以及抗生素去氧羥四環素(DCH)的聚乳酸(PLA-DM)進行混合靜電紡絲以得到複合纖維，透過疏水PLA-DM纖維的加入，能解決Alg太過親水所致的細胞貼附不佳，並且改善Alg硬而易斷的機械性質，使其具適當的柔韌及抗張性。且由於DCH的抗菌效果，複合纖維均能達到高於99.9 %的抗菌率。另一方面，血小板衍生生長因子（PDGFB）基因能與聚乙烯亞胺(PEI)結合形成帶正電奈米顆粒，帶負電的褐藻酸鈉纖維能將其固定以藉此原位轉染貼附的細胞。體外實驗證實轉染細胞所表達的PDGFB能夠促進細胞的增生。將這些複合纖維應用於糖尿病傷口的感染模型，發現在有敷料的應用可以避免生物膜的生成，PLA-DM中的DCH具有良好的抗菌效果，可以避免炎症細胞的浸潤，而混紡纖維因為有固定PDGFB基因，能促進新的表皮生成，並提高傷口修復效果。因此本研究的所開發的傷口敷料確實可降低感染風險並減緩發炎反應，有效促進慢性傷口的修復。;Chronic wounds are at risk of infection due to their slow healing, so multifunctional wound dressings with antibacterial effects and healing promotion are highly demanded. In this study, sodium alginate (Alg) acid and polylactic acid loaded with mesoporous silica nanoparticles (MSN) and antibiotic doxycycline hyclate (DCH), i.e. PLA-DM, were coelectrospun to fabricate composite fibers. Because Alg fibers are too hydrophilic, cells cannot well adhere to their surfaces. The incorporation of PLA-DM fibers reduced poor cell adhesion caused by hydrophilic Alg fibers. Furthermore, PLA-DM also improved the mechanical performance, so that the composite fiber demonstrated appropriate flexibility and tensile strength. Due to DCH loading, composite fibers all demonstrated antibacterial efficacies higher than 99.9%. On the other hand, the platelet-derived growth factor-B (PDGFB) gene complexed with polyethyleneimine (PEI) to form positively charged nanoparticles, which could be immobilized onto negatively charged sodium alginate fibers to in situ transfect adhered cells. The in vitro experiments showed that PDGFB expressed from transfected cells could promote cell proliferation. These composite fibers were applied to treat infected wounds on diabetic mice. Biofilm formation can be avoided by the coverage of wound dressing. Because DCH loaded in PLA-DM can inhibit bacterial infection, the infiltration of inflammatory cells was eliminated. Immobilizing PDGFB genes facilitated the formation of the newly born epidermis and enhance wound repair. Overall, wound dressings developed in this study indeed reduced the risk of infection, relieved inflammation, and effectively promoted the healing of chronic wounds.
