- 學位論文
幾丁聚醣-磷酸鈣複合材之生物降解性研究
Study on Biodegradation of Chitosan-Calcium Phosphate Composites
摘要
組織工程是融合工程學科與生命科學的一門跨領域學科，骨架為組織工程的三大要素之一。組織能否成功的再生或修護依賴著適當骨架的應用，從人工合成或自然物質製造而得的骨架擔任組織暫時功能的代理者。天然高分子材料由於它們優良的生物可分解性、無毒性和生物可吸收性，可作為組織工程用骨架材料，然它們的骨誘導性和機械性質較不好，藉由具良好的骨誘導性和機械性質之磷酸鈣可改善天然高分子缺點。 本實驗以幾丁聚醣為原料，混以不同比例的交聯劑和鈣磷酸鹽在相同溫度下乾燥，製作幾丁聚醣/鈣磷酸鹽複合體。研究幾丁聚醣/鈣磷酸鹽複合體在人工模擬體液下之機械性質與微結構變化，並探討此有機-無機複合體疲勞行為。結果發現各複合體之機械強度隨幾丁聚醣含量而增加，當中以10CHI20T的幾丁聚醣/鈣磷酸鹽複合體具有最高三點彎曲強度，達到54.8 MPa。浸泡人工體液實驗發現40CHI10T的幾丁聚醣複合體的三點彎曲強度從原始未浸泡的17.01 MPa下降到浸泡90天後的2.22 MPa，而重量損失也高達45.85%。微結構指出隨浸泡時間越久，其表面因降解而形成孔洞。疲勞測試結果顯示大部分的幾丁聚醣/鈣磷酸鹽複合體在20-50 MPa荷重下可承受103-104次循環負荷。
並列摘要
Tissue engineering is an interdisciplinary biotechnology consisting of engineering and life science. The scaffolds are one of three important elements in the field of tissue engineering. The regeneration and repair of damaged and injured tissue depends on the appliance of appropriate scaffolds made of the artificial or the natural materials, serving as the substitutes that support and organize the temporary function of tissue. Due to their good biodegradable, nontoxic and bioabsorbable, natural polymer materials such as chitosan, collagen can be tissue-engineered to use as scaffold materials, but are not good in the osteoconductive and mechanical properties. With good osteoconductive and mechanical properties calcium phosphates can improve the defects of polymer materials. In this study, Chitosan matrix was cross-linked with different proportion of glutaradehyde and calcium phosphate to make Chitosan/ calcium phosphate composites after heat drying. The mechanical properties and microstructure of organic/inorganic hybride composites were studied in the physiological simulated solution. More importantly, fatigue behavior of the composites was also evaluated. The results showed the mechanical peoperties of chitosan-based composites to increase with increasing chitosan amounts. The sample of 10CHI20T had the highest bending strength of 54.81 MPa. In immersion experiment, the strength of 40CHI10T descended from 27.01 MPa to 2.22 MPa after 90-day soaking. The weight loss reached up to 45.85%. The immersed surface became more porous because of material degradation with soaking. The fatigue test exhibited that most of the present composites can support the three point bending loading of 20-50 MPa in 103-104 cycles.