臺灣博碩士論文加值系統

本研究主要探討聚乙二醇-聚酯類雙團聯共聚物(mPEG-PLGA及mPEG-PCLA)之物理、化學性質，在固定親水鏈段與疏水鏈段之分子量比例為550/1405的原則下，調整其疏水鏈段中單體與單體之間的莫耳比例，找出作為溫度敏感型水膠材料之最適化條件。實驗利用開環聚合反應製備出雙團聯共聚物，在mPEG-PLGA系列中依疏水鏈段單體比例不同分為L10、L8G2、L6G4、L4G6、L2G8及G10。而在mPEG-PCLA系列當中，也依單體比例不同分為L10、L8C2、L6C4、L4C6、L2C8及C10。結果顯示，L10、L4G6、L2G8、L2C8、G10、C10因其疏水性或結晶性而不溶於水，其餘共聚物L8G2、L6G4、L8C2、L6C4、L4C6於水溶液中皆可形成奈米微胞，臨界微胞濃度小於0.1mg/ml，粒徑皆在100nm以下。然而mPEG-PLGA系列中15wt%水溶液之成膠溫度為15-50℃，成膠範圍很廣；mPEG-PCLA系列則是降解速度較慢，其中L4C6及L6C4，在降解後之第30天，其重量還有原本的60%以上。其中，L6C4為最適化條件，除細胞毒性測試中，顯示20wt%水膠之良好生物相容性，亦在軟骨修復之動物實驗中，展現其水膠載體優良之特性。縱合上述之研究成果，相信此一mPEG-PCLA系列之共聚合物，適合用於原位注射成膠之藥物釋放系統。

The objective of this study is to discuss the thermo responsiveness properties of methoxy poly(ethylene glycol)-polyesters (mPEG-PLGA, mPEG-PCLA) diblock copolymers. Without changing the hydrophilic/hydrophobic segment ratio of the copolymer, the molar ratio of ester monomers was adjusted to obtain better formulation for a thermal-sensitive hydrogel. Diblock copolymers were synthesized using ring-opening polymerization. For the mPEG-PLGA series, L10, L8G2, L6G4, L4G6, L2G8, and G10 were prepared corresponding to LA/GA ratios of 100/0, 80/20, 60/40, 20/80, and 0/100, respectively. For the mPEG-PCLA series, L10, L8C2,L6C4, L4C6, L2C8, and C10 were prepared corresponding to LA/CL ratios of 100/0, 80/20, 60/40, 20/80, and 0/100 respectively. Results showed that L10, L4G6, L2G8, L2C8, C10 and G10 were insoluble in water due to high crystallinity and hydrophobicity. L8G2, L6G4, L8C2, L6C4, and L4C6 formed nanoparticles with sizes under 100 nm and critical micelle concentrations below 0.1 mg/mL in aqueous solution. Also, it was observed that 15 wt% (w/v) mPEG-PLGA displayed a wide gelation window in water.
Adjusting the molar ratio of monomers in mPEG-PLGA did not significantly alter the gelation window while decreasing the LA units in mPEG-PCLA narrowed the gelation window. In degradation test, mPEG-PCLA series showed slower degradation rate, L4C6 and L6C4 both degraded less than 40% of their original weight after 30 days. In brief, L6C4 hydrogel has optimal ratio, which shows good biocompatibility in cytotoxicity test. Also, L6C4 is a promising drug delivery carrier in cartilage defect regeneration model.
These results demonstrate some diblock copolymers of mPEG-PLGA and mPEG-PCLA can be used as in situ gelling drug delivery systems.

摘要 I
Abstract II
表目錄 V
圖目錄 VI
第一章 文獻回顧 1
1.1 生醫材料簡介 1
1.2 生物可分解高分子 2
1.3 水膠簡介 3
1.3.1 水膠的定義 3
1.3.2 水膠分類 4
1.3.3 水膠交聯方式 5
1.3.3.1 化學性交聯 6
1.3.3.2 物理性交聯 6
1.4 溫度敏感型水膠特性 (Thermosensitive hydrogels) 6
1.4.1 LCST定義 8
1.4.2 相轉變行為 (transition behavior) 9
1.5 溫度敏感型水膠材料介紹 11
1.5.1 聚異丙烯丙烯醯胺(poly(N-isopropylacrylamide，PNiPAAm) 11
1.5.2 聚氧化乙烯(PEO)/聚氧化丙烯(PPO)團聯共聚物 12
1.5.3 mPEG-PLGA 12
1.5.4 mPEG-PCL 13
1.6 聚酯類水解機制 15
第二章 研究動機與目的 18
第三章 實驗儀器與設備 20
3.1 實驗藥品 20
3.2 實驗儀器 21
第四章 實驗步驟與方法 22
4.1 實驗架構 22
4.2 mPEG-polyesters 兩團聯共聚物製備 24
4.3 化學結構鑑定及性質分析 27
4.3.1 GPC分析 27
4.3.2 NMR鑑定 27
4.3.3 臨界微胞濃度測定 27
4.3.4 LCST量測 29
4.3.5 微胞粒徑分析 30
4.3.6 水膠相轉變行為測定 32
4.3.7 體外降解及其pH值變化量測定 32
4.4生物相容性測試 33
4.4.1細胞毒性測試(MTT assay) 33
4.4.1.1細胞培養 34
4.4.1.2 測式方法 34
4.4.2溶血試驗(Hemolysis test) [18] 35
4.4.2.1製作標準曲線 35
4.4.2.2 血漿血紅素(Plasma Free Hemoglobin, PFH)濃度測定 35
4.4.2.3全血血紅素(Total Blood Hemoglobin)濃度測定 36
4.4.2.4溶血試驗測定 37
4.5動物實驗 38
4.5.1皮下注射試驗 38
4.5.2軟骨缺損修補 38
第五章 結果與討論 40
5.1 mPEG-polyesters合成 40
5.2 NMR結構鑑定 41
5.3 GPC分子量之量測 45
5.4合成結果探討 46
5.4.1 mPEG-PLGA 46
5.4.2 mPEG-PCLA 48
5.4.3 mPEG-PCGA 49
5.5 臨界微胞濃度(CMC)量測 50
5.6 最低臨界溶解溫度(LCST)量測 52
5.7 微胞粒徑量測 53
5.8 水膠相轉變行為 55
5.9 水膠降解行為及其pH測定 60
5.10生物相容性測試 63
5.10.1 細胞毒性測試(MTT assay) 63
5.10.2溶血試驗(Hemolysis test) 64
5.11動物實驗 66
5.11.1皮下注射試驗 66
5.11.2軟骨缺損修補 68
第六章 結論與未來展望 75
第七章 參考文獻 78
Appendix 80

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