本研究利用雷射加工技術與微機電製程，分別製備聚甲基丙烯酸甲酯(Poly-methyl-methacrylate, PMMA) 微流體晶片與聚二甲基矽氧烷(Polydimethylsiloxane, PDMS)微流體晶片，用於製備幾丁聚醣微纖維絲(Chitosan microfibers)。研究策略是將幾丁聚醣溶液與三聚磷酸鈉溶液注入微流道中，透過鞘流原理於流道交匯處形成幾丁聚醣液體層流，經實驗證實藉操控液體流量可生成不同厚度的層流，在PMMA晶片實驗中，能控制在30~50 µm，而PDMS晶片實驗中則能控制在15~40 µm之間。進一步探討不同角度對層流的生成影響，發現30°角相較60°角具有縮小10%層流厚度的效果。而在三聚磷酸鈉溶液的交聯反應下，幾丁聚醣液體層流能形成幾丁聚醣纖維絲，於本實驗中所製備之纖維絲管徑範圍為20~200 µm。取約80~100 µm左右管徑之幾丁聚醣纖維絲，將膠原蛋白(Collage)沾附表面後進行細胞培養實驗，以幾丁聚醣纖維絲分別與許旺細胞(Schwann cell)及纖維母細胞(Fibroblast cell)共同培養，實驗結果發現許旺細胞能在微纖維絲上增生形成一細胞鏈，而纖維母細胞能在纖維絲上大量增生並將其包覆起來，驗證了幾丁聚醣纖維絲應用在細胞培養上的可行性。

In this study, we fabricated the Poly-methyl-methacrylate (PMMA) microfluidic and Polydimethylsiloxane (PDMS) microfluidic chip by using laser machine and MEMS technologies to generate chitosan microfibers. Our strategy is that the chitosan solution and sodium tripolyphosphate (STPP) solution are pumped into the cross-junction microchannel of the microfluidic chip and the laminar flow of chitosan solution can be generated by the hydrodynamic focusing. By varying the ratio between chitosan solution rates and STPP solution flow rates, the various diameters of laminar flow can be obtained. By controlling core and sheath flow rate, we can generate different diameter of laminar flow from 30~50 µm with PMMA microfluidic chip, and the diameter of laminar flow from 15~40 µm with PDMS microfluidic chip. Cross-junction microchannel with angle 30°、45° and 60° were designed for investigating the influence of the generation of laminar flow. The microfluidic chip with angle 30° microchannel can decrease the diameter of laminar flow with 10% than that with angle 60° microchannel. The laminar flow of chitosan solution transform the chitosan microfibers by cross-linking reaction with STPP solution, and the diameter of chitosan microfiber can be obtained from 20 µm to 200 µm. Then, the chitosan microfiber with diameter of 80~100 µm was chosen as scaffold, and the chitosan microfibers were coated with collage for cell cultivation. In this experiment, the schwann cell and fibroblast cell with chitosan microfibers were used for cell culture. The result of cell culture present that cells proliferate and cover on the surface of chitosan microfibers. This result demonstrates the chitosan microfibers can provide good efficiency for cells, and can be a scaffold for cell culture in tissue engineering application.

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