臺灣博碩士論文加值系統

三維多孔性生物可降解支架已被廣泛應用於組織工程的骨頭修復與再生，支架的主要功能為提供結構讓細胞附著及增生。本研究選用生醫高分子材料Poly-ε-caprolactone (PCL)、致孔劑Sodium Chloride (NaCl)與生醫陶瓷Hydroxyapatite (HA)或nano-alumiun oxide (nAl2O3)混合，經由溶液澆鑄/粒子析出去得到生物多孔性支架。
本研究以生醫高分子材料(PCL)針對PCL, PCL/mHA, PCL/nHA及PCL/ nAl2O3支架並且探討生物多孔性支架之機械特性(壓縮試驗)、物理特性(孔隙率測試、含水率測試、接觸角測試)，爾後以降解實驗來觀察生物多孔性支架之重量損失百分比及pH值變化。細胞測試選擇類骨母細胞(MG63)培養於支架並且進行細胞毒性試驗(MTT)。最後，本研究將支架植入於大鼠股骨，並於第二週及第四週進行組織學觀察。
根據結果顯示，HA與nAl2O3能夠有效的改善材料的親水性質，PCL/nAl2O3有較佳的機械性質。降解實驗結果指出添加nAl2O3可加快降解速率。另外，PCL/nHA支架在體外實驗有較好的生物相容性。體內評估方面，組織學檢測發現PCL/nHA支架在植入兩週後有組織生長及新骨形成之現象。整體而言，PCL/nHA支架在體內有較佳的生物相容性及骨生成性。

Three-dimensional porous biodegradable polymer scaffolds have been widely used for tissue engineering of bone repair or regeneration. The primary function of scaffolds is to provide structure support for the cells adhesion and proliferation. This study selects the Poly-ε-caprolactone (PCL) as material, NaCl mixed with hydroxyapatite (HA) or nano-alumiun oxide (nAl2O3). In addition, this study uses the solution casting/particulate leaching method to fabricate the porous scaffold. This study discusses the compression mechanical properties, physical properties (porosity, moisture content, contact angle) of a pure PCL, PCL/mHA, PCL/nHA and PCL/nHA scaffolds. Subsequence, this study discusses the weight loss and pH values change for degradable experiment on scaffolds. The in vitro cell culture is used for osteoblast cell (MG63) and the Microculture Tetrazolium Test (MTT) is undertaken in the scaffold. Finally, the scaffolds are implanted to the femur of rats and histological examination is attempted after 2 weeks.
The experimental results indicate that HA and nAl2O3 can improve the hydrophilic property. The PCL/nAl2O3 scaffolds have excellent mechanical properties. Results of degradation test reveal that the degradation rate of the scaffolds is accelerated by adding nAl2O3. Results of the MTT test indicate that the PCL/nHA scaffolds have excellent in vitro biocompatibility. In the in vivo evaluation, the PCL/nHA scaffolds show splendid tissue reaction and new bone formation at the 2nd weeks after implantation. In conclusion, the PCL/nHA scaffold exhibits splendid in vivo biocompatibility and osteogenesis.

Chinese abstract I
Abstract III
Acknowledgements V
Contens VII
Nomenclature IX
List of Tables XI
List of Figures XIII
1 INTRODUCTION 1
1.1 Motivation 1
1.2 Literature review 2
2 EXPERIMENTAL METHODS 7
2.1 Preparation of scaffold 7
2.2 Degradation test 9
2.3 Cell culture 10
2.4 In vivo evaluation 12
3 RESULTS AND DISCUSSION 15
3.1 Physical properties of scaffold 15
3.2 Degradation test 17
3.3 Cell culture 19
3.4 In vivo tissue interactions 21
4 CONCLUSIONS AND FUTURE WORKS 25
4.1 Conclusions 25
4.2 Future works 26
REFERENCES 27
APPENDIX A 53
APPENDIX B 56

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