| Abstract: | 本研究使用電氣紡絲法結合雙軸模頭及金屬收集器發現可在一定參數內，成功將電紡絲聚集在收集器之一點上進而得到一類似單晶成長之超高順向中空纖維膜。類似某些半導體材料。當收集時間增加時，纖維開始站立於收集器表面。在掃描式電子顯微鏡觀察下，發現其管與管間的確為一類單晶成長之堆疊情形所產生之膜材，且在用影像處理分析後，亦發現隨著高分子容液濃度增加後，可得到一高度順向之中空電紡薄膜。在使用熱重分析儀與x-ray 散射儀分析後，發現電紡後之纖維與原聚乳酸顆粒有相似之熱性質與結晶度。在外管聚乳酸濃度增加時，亦發現在材料達到高度順向時其機械性質也有增加之趨勢。另外也進而使用生物電紡技術個別加入NIH3T3 ，PC12和牙髓細胞進行實驗，在螢光染色後可觀察到細胞的確能藉由生物電紡技術進入中空纖維管中，並加入神經生長因子(NGF)後，也可觀察到突觸生長。以此超高順向度之中空電紡纖維膜，不但可模擬生物體中之環境，也可提供神經或血管再生之組織工程支架，甚至更多應用。
An electrospinning method and new formulation were developed to prepare novel “epitaxial growth-like” highly aligned, mono-layered micron size hollow fibrous membrane. With a co-axial spinneret and a pair of biodegradable polymeric solutions, common electrospinning parameters and a rotating drum collector, an interesting phenomenon was observed. The electrospun fibers were deposited on the same spot on the rotating drum. These fibers piled up and stood up from the surface of the drum as the collecting time increase. The samples were washed with water for 24 hours. SEM observation revealed sheets of mono-layered micron size hollow fibers membrane. These fibers were well aligned and tightly packed, just like the epitaxial growth of some semiconducting materials. According to TGA and XRD analysis, different PLLA concentration in electrospun hollow fibers resulted in the similar thermal properties and crystalline structure. The morphology of electrospun PLLA hollow fibrous membrane changes from random to highly aligned when the PLLA concentration increased. The highly aligned fibrous membrane has better mechanical properties. NIH3T3, PC-12 and dental pulp cells were added into PLLA hollow fibers respectively via bio-electrospinning technique. The PC-12 cells were successfully added into inner core. Flourescein-transfected PC-12 cells, were observed in the electrospun hollow fibers by fluorescent microscope. After addition of NGF into tubes, PC-12 cells attached to the tube wall. Axons of PC-12 cells were successfully induced. It grow along the tube. This perfectly aligned hollow fibrous membrane is considered as highly anisotropic structure scaffold. It mimics some tissue structures, such as nerve tissue, vascular structure, and could be many other applications as well. |
