- 學位論文
聚酯纖維針織物骨支架製程設計與特性評估
Manufacturing Design and Characteristic Evaluation of Polyester Knitted Fabrics as Bone Scaffold
摘要
生醫材料廣泛應用於製造體內或體外的醫學資材，體內的生醫材料可應用於人工血管、人工骨骼與關節等等。而使用於骨支架之材料，需具備良好生物相容性且需製備成具有適當的機械強度與孔洞大小，以利於骨組織貼附和向內生長之骨支架。因聚酯纖維與鈦棒皆具有良好的機械性質，幾丁聚醣則具有良好的生物相容性及無毒性，故本研究將設計以聚酯纖維與鈦棒製成具有適當的機械強度與孔洞大小之人工複合骨支架，並添加幾丁聚醣藉以增加支架和組織之間的相容性。 本研究將以聚酯長絲為包覆材，鈦棒為芯材，並修正兩種材料後處理的最佳參數值製備成複合人工骨支架。首先將聚酯長絲經併股與加撚加工製備成PET股線，再分別織成多孔性3 D針織物並作層數的變化及鹼處理，再將針織物浸泡於幾丁聚醣溶液中，以冷凍乾燥方式製備成3 D多孔PET/幾丁聚醣圓管針織物。接著將鈦棒作鹼、熱處理，再以電化學法來沉積氫氧基磷灰石後，將樣本浸泡不同天數之模擬體液，增加氫氧基磷灰石之鈣磷比。最後PET/Ti/幾丁聚醣經最佳化參數後處理製程的加工成複合人工骨支架後，分別進行一系列機械性質、實體顯微鏡、SEM、EDS、XRD、FTIR、降解率、重量增加率、pH值測試評估後，最後再進行骨母細胞(MG63)培養及體內測試評估。 研究結果顯示，藉由PET長絲織成3 D圓管針織物，再進行層數的變化及以1wt %的幾丁聚醣溶液處理，使針織物具備3 D多孔與穩定的結構；而鈦棒經由鹼熱處理及電化學沉積60分鐘後，得知在熱處理400 ℃時具有良好的沉積量及鈣磷比；以此兩者最佳參數進行複合，製備成3 D多孔複合PET/Ti/幾丁聚醣人工骨支架，細胞培養結果顯示具有良好的細胞存活率與貼附性。最後以大鼠脛骨鑽孔直徑2 mm，並將本研究研製之複合支架植入六週後，經x光判讀實驗結果顯示脛骨鑽孔的孔洞大小有明顯的縮小情形，發現在第六週組織切片顯示PET/Ti/幾丁聚醣人工複合骨支架已有良好的生物相容性及骨誘導性。
並列摘要
Biomaterials are commonly used as in vitro or in vivo. Synthetic vascular prostheses, artificial bones, and artificial joints are used in vitro. Bone scaffolds demand components with good biocompatibility, mechanical strength, and pore size to help the bone tissue attach to them and allow them to be ingrown. Polyethylene terephthalate (PET) filaments and titanium (Ti) bars both have good mechanical properties while chitosan has good biocompatibility and is non-toxic. Therefore, this study combines these two materials to make the bone scaffolds with appropriate mechanical strength and pore size, after which they are immersed in chitosan solution for a better biocompatibility between the bone scaffolds and tissues. This study uses PET filaments to wrap the titanium bar, forming the composite artificial bone scaffold with optimum parameters. First, the PET filaments are combined and twisted into plied yarns, and then braided into three-dimensional knitted fabrics. The knitted fabrics, made with various layers, undergo alkali treatment, immersed in chitosan solution, and then freeze-dried, forming the three-dimensional, porous and hollow PET/chitosan knitted fabrics. Second, by electrochemical deposition method, Ti bars that receive alkali treatment and heat treatment can attract phosphate, and are then immersed in the simulated body fluid (SBF) for different days to increase the calcium-phosphorus (Ca/P) ratio of hydroxyapatite. Third, PET knitted fabrics and Ti bars with the optimal parameters are combined and then immersed in chitosan solution, forming the PET/Ti/chitosan bone scaffolds. The resulting bone scaffolds are observed or tested by a stereo microscope, scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and then evaluated for mechanical properties, degradation, weight increase rate, and pH value. Finally, the bone scaffolds are co-cultured with osteosarcoma cells (MG63) and in vivo test. According to the experimental results, the change in layer number and the immersion in 1 wt% chitosan solution give the PET knitted fabrics a stable structure. Ti bars yield good deposition amount of hydroxyapatite and Ca/P ratio after the alkali treatment, heat treatment, and electrochemical deposition method for 60 minutes, determining the optimal temperature for heat treatment is 400℃.These two materials of optimal parameters are then combined to form the three-dimensional, hollow bone scaffolds. The result of cell culture shows that the resulting bone scaffolds have good cell viability and cell attachment. Finally, the rats are drilled a hole of a 2-mm diameter in their tibia bones and then implanted with the bone scaffolds. After six weeks, X-ray interpretation shows that the holes in the bones significantly become smaller; at the same time, the tissue slice indicates that PET/Ti/chitosan bone scaffolds have desired biocompatibility and osteoinduction.