臺灣博碩士論文加值系統

利用手術縫合治療阿基里斯肌腱斷裂方法仍需改進的技術。因此，要解決肌腱斷裂後修復上的缺陷，可利用組織工程的方法來改進。本研究目的為探討電紡絲製備過程中，不同參數對聚乳酸-甘醇酸纖維直徑和型態的影響，以及所製備出電紡支架對肌腱纖維母細胞活性及型態的影響。電紡纖維支架形成是經由電場所提供的靜電力抽絲而成。結果顯示，控制不同的電紡參數，可得到不同直徑和形態的纖維。本研究可製備出纖維直徑範圍在144 ± 22 nm 到 1247 ± 71 nm，孔洞大小為5-10 μm2 具有 50% 孔洞率的支架。在三個參數下，以聚合物濃度和注射速率對纖維直徑和表面型態影響最大，電場強度則較無明顯的影響。將最佳化的支架來評估阿基里斯纖維母細胞生長情形，結果顯示所製備不同纖維直徑的聚乳酸-甘醇酸支架提供細胞良好的貼附性，快速的生長速率和基因表現量，且可以維持細胞正常成長型態。因此，所製備出的聚乳酸-甘醇酸奈米纖維對於阿基里斯腱具有組織工程發展上的潛力。

The treatment of the ruptured tendon is still an obstacle in respect of suture method. Therefore, such shortcoming in repairing fracture tendons could be overcome through tissue engineering approaches. The aim of present study is to investigate the influence of processing parameters on poly(lactide-co-glycolide) ( PLGA) scaffold morphology and fiber diameters and the effect of the tendon fibroblast with the obtained novel tissue engineering electrospun-PLGA. The result shows that the electrospun scaffold diameter and morphology could be controlled under different processing parameters, such as PLGA concentration, applied electric voltage and solution pumping rate. Electrospun-PLGA in the range of 144 ± 22 nm to 1247 ± 71 nm in diameter were obtained under different processing parameters. By varying the above parameters, the electrospun porous PLGA scaffolds exhibited fibrous morphology either with or without beads. The diameter of electrospun scaffold increased with the PLGA concentration and pumping rate, whereas the electric field strength exerted only minor effect on the average diameter of the electrospun scaffold. The cytocompatibility of the scaffold prepared from optimizing fabrication parameters was evaluated using Achilles tendon fibroblasts. Good results in cell attachment, cell proliferation rate, fibroblast morphology, and gene expression with various sizes of electrospun fibers were observed. Therefore, electrospun PLGA scaffold have the potential for Achilles tendon repair.

ABSTRACT I
摘要 II
ACKNOWLEDGEMENTS III
TABLE OF CONTENTS IV
LIST OF FIGURES VII
LIST OF APPENDIX FIGURES IX
LIST OF TABLES XI
Chapter 1. Introduction 1
1.1 Function and structure of tendon tissue 2
1.1.1 Function of tendon tissue 2
1.1.2 Components of tendon tissue 3
1.1.3 Gross structure 5
1.2 Tissue engineering for tendon repair 7
1.3 The characteristic for electrospun nanofiber 9
1.4 The technique of electrospinning 9
1.5 Poly(lactide-co-glycolide) (PLGA) 13
1.6 Recent studies of Achilles tendon repair worldwide 14
1.7 Specific aim 18
Chapter 2. Material and method 19
2.1 Flowchart of experiment 19
2.2 Materials and instrument 20
2.3 Electrospun-PLGA scaffold fabrication 22
2.4 Fiber morphology 23
2.5 Fiber degradation test 24
2.6 Biological investigation for electrospun-PLGA scaffold/tendon fibroblast 24
2.6.1 Cell culture of Achilles tendon fibroblasts 24
2.6.2 Cell seeding on electrospun-PLGA scaffolds 25
2.7 Cell biocompatibility and viability assay 25
2.7.1 Cell biocompatibility assay 25
2.7.2 Cell viability assay 26
2.8 Cell morphology 26
2.9 Real-time quantitative PCR analysis 26
2.9.1 RNA isolation 26
2.9.2 cDNA synthesis 27
2.9.3 Real-time quantitative PCR and primer synthesis 27
2.10 Statistical analysis 28
Chapter 3. Results 29
3.1 Fiber morphology 29
3.2 Fiber diameter 32
3.3 Fiber pore size and surface porosity 35
3.4 Fiber degradation test 40
3.5 Cell biocompatibility 44
3.6 Cell viability 46
3.7 Cell morphology 48
3.8 Gene expression 51
3.8.1 Primer efficiency Analysis 51
3.8.2 Normalized amount of gene expression 54
3.9.1 The process parameters of electrospinning 56
3.9.2 The inadequate mechanical strength of scaffold 56
Chapter 4. Discussion 57
4.1 Fiber morphology and diameter 57
4.1.1 Effect of PLGA solution concentration 57
4.1.2 Effect of pumping rate 58
4.1.3 Effect of electric field strength 58
4.1.4 Comparison of the influence of different Parameters on fiber diameter 59
4.2 Fiber pore size and surface porosity 65
4.3 Fiber degradation test 68
4.4 Cell biocompatibility and viability 69
4.5 Cell morphology 70
4.6 Gene expression 71
Chapter 5. Conclusion 73
REFERENCE 75
APPENDIX A 85
APPENDIX B 97

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