慢性傷口因癒合時間較長，需要開發抗菌敷料來避免感染風險。聚乳酸(PLA)為常見敷料材料，具有可降解性以及生物相容性，然而其疏水性使其不易包覆藥物及持續釋放，因此本研究將介孔二氧化矽奈米粒子(MSN)混入PLA進行電紡絲，以用於裝載抗生素去氧羥四環素(DCH)。透過測試發現MSN的加入不但能夠增加纖維的熱穩定性也能增加機械強度，且纖維具有高透氣性，可以有效保護傷口。經由溶脹率實驗結果了解到MSN結構上的氫氧基能增加親水性，使得溶脹率提高，此特性不但能促進傷口滲出液的吸收，也有助於改善纖維的高疏水性。因此在藥物釋放實驗中，DCH的釋放會隨著MSN在纖維中的比例而提升。其中D-P-M12會造成初始爆發釋放，因此對成纖維細胞造成明顯毒性，但此毒性並未在其他載藥複合纖維發現。最後，在抗菌實驗中證實，雖然D-P-M12的初始爆發釋放使其在紙錠擴散實驗中擁有最大的抗菌抑制區，但其效果會隨時間下降，相較之下，D-P-M10組即使到了第四天都可以維持99%的抗菌效果，因此考量到穩定的抗菌能力及不會影起細胞毒性，D-P-M10纖維極具成為慢性傷口敷料的潛力。;Considering the long healing time of chronic wounds, it is necessary to develop antibacterial dressings to avoid the risk of infection. Polylactic acid (PLA) is a frequently investigated dressing material due to its biodegradability and biocompatibility. However, its hydrophobicity makes it difficult to load drugs for sustained release. Therefore, in this study, mesoporous silica nanoparticles (MSN) were mixed with PLA to electrospin composite nanofibers for loading doxycycline hyclate (DCH), an antibiotic. These fibers owned high permeability. In addition, the added MSN not only increased thermal stability but also reinforced composite nanofibers, suggesting that composite fibers were suitable to physically protect wounds. The hydroxyl groups on MSNs increased the hydrophilicity to enhance the swelling rates of composite fibers, which not only promoted the absorption of wound exudate but also improved wettability of the composite nanofiber. Therefore, the release experiments showed that DCH delivery increased with the ratio of MSN in the composite nanofibers. Among them, D-P-M12 demonstrated an initial burst release, which thus significantly reduced proliferation rates of fibroblasts. However, other composite fibers did not occur this difficulty. Regrading antibacterial effects, D-P-M12 owned the largest inhibition zone in disc-diffusion experiments due to its initial burst release, but its antibacterial efficiency decreased over time. In contrast, the D-P-M10 group maintained 99% of antibacterial effects for 4 days. Therefore, D-P-M10 fibers were potential dressings for chronic wounds due to its stable antibacterial ability without causing cytotoxicity.
