心肌、平滑肌、骨骼肌、與神經細胞等，在人體內皆為順向性地排列生長。這類細胞在體外進行組織工程的培養時，若能保持同樣的順向形態，將可使細胞表現出接近於體內生長時的正常功能。本研究利用金屬管尖端作為電紡收集端，製備出具有高度順向性的微米纖維束，作為導引細胞順向生長的支架，讓細胞的形態和原生組織更為相似。為了要克服傳統三維細胞培養系統的氧氣與養份質傳阻礙問題，本研究進一步把電紡纖維束和氧化鐵(Fe3O4)奈米粒子結合，製備出具有超順磁性之微米纖維束，將細胞種在纖維束上，藉由外加磁場驅動，將small size的細胞束重組，以得到large scale的三維順向性細胞柱。本研究主要分為兩大部份，第一部分為尋找最佳電紡溶劑組成，並探討纖維束的細胞毒性。由實驗結果得知，六氟異丙醇與二氯甲烷[HFIP/DCM = 75/25 (v/v)]之混合溶劑，為電紡聚乳酸甘醇酸(PLGA)與Fe3O4奈米粒子的最佳溶劑。經由體外培養實驗得知，將老鼠骨骼肌肌母細胞(C2C12 myoblast)種在所製備的PLGA纖維束上，C2C12細胞可正常貼附並順向性生長，且沒有明顯地細胞毒性。第二部分主要是製備出具有順磁性的纖維束，並探討C2C12細胞於此纖維束上分化與增生之情形。由TEM觀察結果得知，超順磁性的Fe3O4奈米粒子，能在PLGA纖維中的均勻分散。由樣品振盪磁測儀(VSM)和超導量子干涉元件(SQUID)等量測結果可證實所製備的纖維束仍具有超順磁性。將細胞種在此順磁性纖維束(含有10% w/w Fe3O4)上，C2C12細胞可被成功誘導成肌小管(myotube)細胞，證實所添加的Fe3O4並不會影響到細胞原來之分化特性。最後，以SEM證實，在磁場的驅動下，small size的順向性細胞束，確實可自組裝成large scale三維細胞柱。進一步以螢光免疫染色證實，能形成緊密黏合的large scale三維細胞柱，是由於相臨細胞間所分泌的fibronectin 和 collagen III 等細胞外間質和黏合蛋白的作用所導致。以上的實驗結果顯示，本研究成功開發出具有超順磁性的纖維束，能在外加磁場驅動下，自我組裝成large scale的三維順向性細胞柱，將來很有潛力應用於肌肉或心肌組織工程修復上。

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