本研究之裝置為微流懸吊式液珠裝置(microfluidic hanging droplet platform)，此為一微流道結構並結合數個對外的開孔，在通入流體後便可藉由對外開孔形成數個懸吊液珠。此裝置在載入含有細胞的培養液後，細胞可以在形成的懸吊液珠中聚集。此裝置不同於一般細胞培養的方法，其細胞之生長型態為球狀結構，而一般培養方式的細胞則會因為貼附在培養皿底部而形成片狀結構。培養環境不同會導致細胞在基因表現、藥物刺激等特徵有著截然不同的表現，而此裝置便是為了製造出更符合體內環境的培養方法。
在此應用下，液珠的形成條件以及穩定度便是重要的考量。液珠形成便是透過表面張力以及重力之間的平衡而穩定。在考慮表面張力的情形下，透過解析解去描述液體運動的現象是十分複雜的方式，也因此需要透過模擬軟體的輔助做視覺化的展示以及分析。在本研究中利用 ESI-CFD 此有限元素分析套裝軟體來模擬本裝置中液體流動之行為，透過此軟體之模擬結果了解液體與裝置(開孔大小、材料的親疏水性)之間的關係，並進行實驗量測此裝置所形成液珠其最大可承受之壓力，用以驗證模擬的趨勢。
透過模擬軟體的結果，在形成液珠所需要之最小壓力到液珠能維持穩定的最大壓力，這段可操作壓力區間可透過將裝置材料改質為較親水性的特性而獲得改善，並且發現開孔直徑 500 µm 所形成的液珠體積以及液珠對於外界影響之穩定度較其他孔徑(50 µm、100 µm、200 µm)佳。在實驗上的結果，由於此裝置材料會吸水的特性，使得表面變為更親水性，而破裂壓力較預測值低，為此透過模擬找出破裂壓力與接觸角之關係，預測材質之接觸角度落在50度至80度之間，也透過實驗驗證了模擬之預測無誤。

This work reports numerical and experimental investigations of a microfluidic hanging droplet platform, in which hanging drops (HDs) are generated automatically through openings at the bottom of a microfluidic channel for sustained three-dimensional (3D) cell culture.
The simulation approach is based on the solution of the free surface equilibrium problem by the finite element method. In contrast to analytical solutions, it provides solutions to the critical advancing angle when the meniscus deforms due to an external driving pressure and proceeds on the wall of an expanding channel.
Microfluidic HD systems have been fabricated in polydimethyl-siloxane (PDMS) by using soft lithography and PDMS membrane transferring techniques for testing the burst pressure. However, we found the discrepancy of the burst pressure between experiment results and numerical predictions, and it was due to the change of PDMS surface property. Thus, we had changed the contact angle of PDMS in simulation boundary conditions and found the trend of simulation results matched the experimental investigations.

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