本研究欲利用電紡絲技術製作聚乙烯醇(poly(vinyl alcohol)，PVA)奈米纖維用於生醫應用，研究上包含進行電紡絲系統的架設以及測試電紡絲噴射的參數，最後以調整好之電紡絲實驗參數進行細胞支架以及作為磁顆粒載體進行磁顆粒釋放之應用。
以聚乙烯醇電紡絲作為細胞支架部份的實驗，使用戊二醛作為交聯劑以增加其抗水性與機械強度，再以傅利葉轉換紅外光譜證實交聯前後之官能基的差異，並將聚乙烯醇與明膠混和進行共電紡絲產生較利於細胞貼附之支架。當3T3纖維母細胞培養於交聯後聚乙烯醇與聚乙烯醇/明膠電紡絲支架後，以螢光顯微鏡及電子顯微鏡觀察可見細胞貼附於各別支架時的形貌差異；當細胞於聚乙烯醇/明膠支架上培養後可完全伸展附著，而於聚乙烯醇電紡絲支架上則形成球狀細胞。實驗上，又利用平行接地電極使電紡絲因電場平行分布而規則排列成線狀，當以聚二甲基矽氧烷（Polydimethylsiloxane，PDMS)作為各別接地電極的支撐面，可形成懸空的平行電紡絲支架，與細胞培養後具有引導細胞生長成線狀之特性。
以電紡絲作為磁顆粒載體進行磁顆粒釋放的研究上，將聚乙烯醇溶液摻以兩種不同磁流體並調整不同濃度後，以電紡技術製備攜帶磁性顆粒之奈米絲，再利用掃描式電子顯微鏡及穿透式電子顯微鏡觀察磁奈米絲之表面型態與其內部顆粒分布，後使用普魯士藍呈色法定量磁性奈米絲於培養基中釋放之磁顆粒量，結果顯示磁顆粒會在初期階段快速釋放，而後於16小時左右即達到飽和，且摻雜磁流體之比例越多其釋放量越高，當此培養基與細胞共培養後以普魯士藍染色法可觀察到胞內磁顆粒量隨釋放量增加。

The purpose of this study was to fabricate polyvinyl alcohol (PVA) nanofibers by the electrospinning technique for biomedical applications. An in-house build setup was used and parameters were optimized to generate nanofibers as cell scaffolds and magnetic nanoparticles carrier matrix.
In the experiment of cell scaffolds, glutaraldehyde was used as a crosslinking reagent to improve mechanical strength and water resistance of the PVA fibers. The changes of functional groups after crosslinking were checked by fourier transform infrared spectroscopy (FTIR). To increase cell adhesion, gelatin was co-electrospun with PVA and NIH 3T3 fibroblast cells were seeded on scaffolds. The morphology of cells analyzed by scanning electron microscope (SEM) and fluorescence microscope were distinct; for those on gelatin/PVA scaffolds stretched extensively, while for those on PVA scaffolds formed spheroids. Parallel grounding electrode attached to PDMS producing parallel-aligned nanofibers was further used as suspended scaffold for cell culture and gelatin/PVA fiber could guide fibroblast cells to form spindle shape. In the other experiment, two kinds of ferrofluid were added to PVA solution to produce magnetic nanofibers. SEM and transmission electron microscopy (TEM) were used to characterize magnetic nanofibers. The amount of magnetic nanoparticles released from magnetic nanofibers was quantified by colorimetric assay, which showed an initial burst release and achieved saturation after 16 h. Intracellular magnetic nanoparticles were visualized by pruissian blue stain and depended on the amount of ferrofluid released from nanofibers.

圖表目錄 5
摘要 8
Abstract 9
誌謝 10
第一章 緒論 11
1-1 研究背景 11
1-2 研究動機與目的 12
第二章 理論基礎與文獻回顧 13
2-1 電紡絲原理簡介 13
2-1-1 電紡絲材料之生醫應用 20
2-1-2 電紡架構設計 22
2-2 聚乙烯醇(PVA)電紡絲 24
2-2-1 PVA性質 24
2-2-2 PVA電紡絲參數回顧 29
2-2-3 PVA交聯機制 36
2-3 PVA/gaelatin電紡絲細胞支架 37
2-3-1 電紡絲細胞支架 37
2-3-2 明膠(gelatin) 40
2-3-3 明膠電紡絲細胞支架 41
2-4 磁纖維絲 43
2-4-1 磁性材料 43
2-4-2 磁滯現象 (Hysteresis) 45
2-4-3 磁性顆粒生醫應用 47
2-4-4 生醫磁性電紡絲 49
2-4-5電紡絲藥物釋放 50
第三章 試驗設備與方法 52
3-1 化學藥品 52
3-2 實驗步驟 53
3-2-1 靜電紡絲系統架設 53
3-2-2 PVA電紡絲製備及交聯反應 53
3-2-3 傅利葉轉換紅外光譜(FTIR)量測樣品表面官能基 54
3-2-4 PVA/明膠細胞支架製備 54
3-2-5 懸空細胞支架 56
3-2-6 細胞存活度計算 57
3-2-7 掃描式電子顯微鏡(SEM)樣品製備與表面形貌觀察 58
3-2-8 磁纖維製作 59
3-2-9 穿透式電子顯微鏡(TEM)樣品製備與磁顆粒分散觀察 59
3-2-10 磁顆粒釋放檢測 60
3-2-11 磁纖維與細胞共培養 60
第四章 實驗結果與討論 61
4-1 電紡絲系統架設 61
4-1-1 參數測試及形貌觀察 61
4-2 細胞支架 64
4-2-1 支架形貌觀察 64
4-2-2 細胞支架生物相容性 66
4-2-3 懸空細胞支架 68
4-3 聚乙烯醇(PVA)電紡絲釋放磁顆粒之研究 69
4-3-1 磁纖維形貌觀察 69
4-3-2 磁顆粒釋放 71
4-3-3 細胞共培養磁纖維 72
第五章 結論與未來工作 74
5-1 結論 74
5-2 未來展望 74

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