本論文主旨為探討以靜電紡絲技術製備三維具有方向性奈米纖維導管支架，並將其應用於生醫領域組織工程之細胞導管。方向性奈米纖維是由聚己內酯（Polycaprolactone，簡稱 PCL）、聚乙烯氧化物（Polyethylene oxide，簡稱 PEO）以及幾丁聚醣（Chitosan，簡稱 CS）三種生物性材料所組成，從中討論方向性奈米纖維的基本性質與觀察三維導管支架導引細胞生長與貼附的情形。
論文首先利用黏度計與電導度計探討PCL/PEO/CS溶液之基本性質，觀察到隨CS含量的增加，溶液之黏度與電導度皆有增加的趨勢，從中決定出最合適的PCL/PEO/CS溶液比例為30 wt% PCL / PEO ( 3：2 ) + 0.7 g CS。
接著利用掃描式電子顯微鏡(SEM)觀察環境與製程參數對於靜電紡絲PCL/PEO/CS方向性奈米纖維的影響，其靜電紡絲PCL/PEO/CS方向性奈米纖維的最佳條件為固定輸出電壓18 kV、溶液流速0.021 ml/min、收集纖維距離12 cm、收集寬度3 cm、收集滾輪轉速1600 r.p.m.以及環境溫度30℃。從中進一步利用示差掃描式熱卡計(DSC)與X光繞射分析儀(XRD)觀察到PCL/PEO/CS奈米纖維隨滾輪轉速越快，纖維高分子之相對結晶度有增加的趨勢。
將製備完成的PCL/PEO/CS方向性奈米纖維藉由二異氰酸己烷(1,6-Diisocyanatohexane，簡稱HDI)交聯後，利用全反射紅外線光譜儀(ATR)觀察N-H特徵峰在1640 cm-1的表現，並且以長期抗降解性、膨潤性、抗拉強度評估其纖維的機械性質，觀察到交聯之PCL/PEO/CS方向性纖維抗降解性能較好、抗拉強度提升以及膨潤性較差，這與交聯機制相符合，但藉由SEM觀察到交聯後之纖維表面發生黏結、孔隙減少，這可能會影響細胞活性與貼附，進而改以雙層PCL/PEO＋PCL/PEO/CS方向性奈米纖維導管結構增加其抗拉強度。
本研究亦將方向性奈米纖維依纖維對齊方向製備成三維具有方向性奈米纖維導管。進一步的將其導管進行纖維母細胞的體外細胞培養實驗，觀察到細胞於本研究之三維具有方向性奈米纖維導管上有良好的細胞活性，這也表示其導管對於細胞沒有毒性，並且從SEM觀察到細胞依纖維對齊方向進行貼附，表示PCL/PEO/CS三維具方向性纖維導管支架具有導引細胞生長促使組織的再生。
關鍵字：靜電紡絲、方向性奈米纖維、組織工程、細胞導管

The purpose of this study was to design and fabricate biodegradable conduits with aligned ultra-fine fibrous structures by electrospinning of polycaprolactone (PCL)/polyethylene oxide (PEO)/chitosan(CS) and characterize the properties of the biodegradable conduits with aligned ultra-fine fibrous structures. The conduit is used in the biomedical field of tissue engineering cell conduit and observe the case of conduit guide cell growth and affixed.
At first, the basic properties of the PCL/PEO/CS solution was observed with viscometer and conductivity meter, and found to increase with the content of the CS, the trend of increase in viscosity and conductivity of the solution. The optimal PCL/PEO/CS solution was at the ratio of 30 wt% PCL / PEO ( 3:2 ) + 0.7 g CS. The best conditions of manufacturing PCL/PEO/CS aligned ultra-fine fibrous structures were (1) the working voltage of 18 kV, (2) flow rate 0.021 ml/min, (3) collection fiber distance of 12 cm, (4) roller speed of 1600 r.p.m., and (5)30 °C. From further use of differential scanning calorimeter (DSC) and X-ray diffractometer (XRD) to investigate the impact between the aligned ultra-fine fibrous and the crystallinity of the polymer, it was found that with the collection of the roller the faster the speed, the longer the fiber directional, relative degree of crystallinity of the better. In addition, the cross link of PCL/PEO/CS aligned ultra-fine fibers by cross-linking agent (1,6-Diisocyanatohexane) solution was examined, too.
The chemical analysis, mechanical strength and biodegradation of the aligned ultra-fine fibers with or without cross link were characterized using FT-IR spectroscopy attenuated total reflectance(ATR), long-term resistance to degradation of performance evaluation, swelling index and tensile test machine.
Finally, we use fibroblast to observe cell morphology and proliferation on the biodegradable conduits with aligned ultra-fine fibrous structures. The results show that the biodegradable conduits with aligned ultra-fine fibrous structures have potential in the application of artificial cellular conduits.

Keyword：Electrospinning, Aligned ultra-fine fibrous structure, Tissue engineering, Cellular conduits

中文摘要 i
ABSTRACT ii
誌謝 iii
目錄 iv
表目錄 vi
圖目錄 vii
第一章、 緒論 - 1 -
1.1 前言 - 1 -
1.2 三維導引支架 - 3 -
1.3 研究動機與目的 - 4 -
第二章、 文獻回顧 - 6 -
2.1 奈米纖維 - 6 -
2.2 靜電紡絲技術 - 7 -
2.3 影響靜電紡絲技術之參數 - 8 -
2.3.1.1 聚合物之分子量 - 9 -
2.3.1.2 濃度與黏度 - 11 -
2.3.1.3 溶劑 - 13 -
2.3.1.4 表面張力 - 14 -
2.3.1.5電導度 - 15 -
2.3.2 製程參數 - 16 -
2.3.2.1 電壓 - 16 -
2.3.2.2 溶液流速 - 17 -
2.3.2.3 針頭至收集處距離 - 18 -
2.3.2.4 收集器的種類 - 18 -
2.3.3 環境參數 - 21 -
2.4.1 幾丁聚醣( Chitosan ) - 22 -
2.4.2 聚己內酯(Polycaprolactone) - 24 -
2.4.3 聚乙烯氧化物 (Polyethylene oxide) - 25 -
2.5 組織工程(Tissue engineering) - 26 -
2.5.1 方向性纖維導管組織支架 - 27 -
第三章、 實驗內容與方法 - 29 -
3.1 實驗藥品 - 29 -
3.2 實驗儀器 - 31 -
3.3 實驗流程 - 34 -
3.4 溶液製備 - 35 -
3.4.1 溶液性質檢測 - 37 -
3.4.1.1 黏度 - 37 -
3.4.1.2 電導度 - 37 -
3.5 靜電紡絲裝置與工作參數 - 38 -
3.6 超細纖維墊交聯 - 39 -
3.7 材料基本檢測 - 41 -
3.7.1 熱性質分析-DSC - 41 -
3.7.2 結晶性分析-XRD - 43 -
3.7.3 官能基鑑定-ATR - 45 -
3.7.4 表面型態分析-SEM - 46 -
3.7.5 長期抗降解性分析 - 48 -
3.7.6 膨潤性分析-吸水率 - 49 -
3.7.7 機械性質分析-抗拉強度 - 49 -
3.8 三維導管支架的製備 - 50 -
3.9 體外細胞分析實驗 - 51 -
3.9.1 體外細胞分析實驗流程 - 51 -
3.9.2 細胞活性與毒性測試(MTS assay) - 54 -
第四章、 結果與討論 - 56 -
4.1溶液基本性質 - 56 -
4.1.1溶液的製備與設計 - 56 -
4.1.2 溶液黏度與電導度 - 61 -
4.2 靜電紡絲參數設定 - 62 -
4.2.1 環境溫度 - 62 -
4.2.2 溶液流速 - 62 -
4.2.3 收集距離 - 66 -
4.3 方向性纖維對齊程度 - 72 -
4.4 滾輪轉速與纖維結晶度的關係 - 76 -
4.4.1 DSC分析 - 76 -
4.4.1 XRD分析 - 78 -
4.5 纖維交聯 - 80 -
4.6機械性質分析 - 83 -
4.6.1 抗降解性能評估 - 83 -
4.6.2 膨潤性能評估 - 85 -
4.6.3 抗拉強度評估 - 86 -
4.7 體外細胞培養 - 91 -
4.7.1 細胞活性與毒性測試(MTS assay) - 91 -
4.7.2 細胞貼附 - 94 -
第五章、 結論及未來方向 - 99 -
5.1 結論 - 99 -
5.2 未來方向 - 101 -
附錄 - 102 -
參考文獻 - 106 -

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