本研究利用微機電系統製程技術之灌注成形法以及微壓印技術，完成聚二甲基矽氧烷(Polydimethylsiloxane, PDMS)微流體濃度梯度晶片之製備，以應用於內皮細胞對葡萄糖最適濃度之研究。研究策略為利用微混合器及多層分流微結構以於PDMS微流道產生一濃度梯度效應，且比較不同流速對於濃度梯度效應之影響；另外，再透過細胞貼附區寬度為300 μm且間距為200 μm之壓印圖形，以探討在不同葡萄糖濃度梯度(0~10%、0~20%、5~15%、6~17%)下，對於內皮細胞之最適濃度。經實驗驗證在不同流速(20、30、40、50 μL/min)下濃度梯度皆呈現穩定分佈，流速超過20 μL/min進行實驗時，因流速過快會造成細胞脫落之現象，且內皮細胞對於葡萄糖之最適濃度為7~15%，而當葡萄糖濃度過高或過低於此最適濃度值時皆會造成內皮細胞萎縮或凋亡之現象。故本研究所建立的微流體濃度梯度晶片系統，不但可解決傳統藥物濃度調配上相當費時且無法於同一實驗區內進行多種濃度測試的問題，在未來將有助於藥物濃度測試及藥物過敏測試等應用領域的發展

In this study, the Polydimethylsilcoxane (PDMS) concentration gradient microfluidic chip and PDMS stamp are fabricated by MEMS, casting molding, and microimprinting technology. The chip is used to research optimizing concentration of endothelial cells on glucose concentration gradient. The experiment strategy is based on a microfluidic network to generate a concentration gradient in solution, and observes the effect of concentration gradient in different flow rates. Besides, it combines micropatterns that cell adhesion space width with 300 μm and gap with 200 μm to discuss the optimizing glucose concentration (0~10%, 0~20%, 5~15%, 6~17%) of endothelial cells. Through the experiment data, we can prove that the concentration gradients are all stable under different flow rates (20, 30, 40, 50 μL/min), however, when flow rates are over 20 μL/min, cell leaves substrate surface. The result shows that the glucose concentration gradient in the 7~15% is the optimizing concentration of endothelial cells, nevertheless, too high and low concentration will lead cell to leave or die. This study can solve the problems of the different drug concentrations prepare and test. It will apply drug concentration test and hypersensitive test in the future.

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