細胞培養是生物與醫學研究不可或缺的一項技術。一般的細胞培養方法將細胞置於培養皿中並提供培養液供細胞生長。在這樣的環境之下，大多數的細胞會附著在培養皿的底面形成單一層細胞的二維結構。然而生物體內的細胞是以三維結構方式生長，並且和其周圍細胞與細胞外間質(extracellular matrix)有緊密的互動。也因此，許多學者認為讓細胞在三維的培養環境中進行實驗所獲得的結果，較能代表細胞在體內的真實行為。然而傳統三維細胞培養技術仍存在許多限制必須克服，才能有效實現三維細胞培養之應用。
本論文希望發展一項新穎的"微流懸吊式液滴(Microfluidic Hanging Droplet) "細胞培養技術，傳統懸吊式液滴技術是藉由將細胞培養在懸掛倒吊的水滴中，由水的表面張力和細胞的自我聚集(aggregate)能力導致3D的細胞生長結構。相較於其他的3D培養細胞方法，懸吊式液滴培養方法有著成本便宜、操作原理簡單、對外開放空間和方便觀測生長中的細胞等許多優點。然而傳統的懸吊式液滴技術每個液滴能夠提供給細胞養分的培養液有限，也因此細胞在液滴內生長的時間也受到限制。因此為了克服傳統懸吊式液滴技術的瓶頸，本論文希望發展一項新穎的”微流懸吊式液滴(Microfluidic Hanging Droplet)”細胞培養技術，我們將懸吊式液滴培養方法和微流道技術做結合，利用穿透微流道底部的孔洞形成懸吊液滴，並以擴散方式讓液滴內細胞生長所需的養分與產生之代謝物和微流道內流動的培養液進行置換。 由於孔洞大小為微米等級，成型的液滴不會輕易的破裂或溢出，並且能以流速之方式加以控制。
本論文所發展之微流懸吊式液滴技術不但可以解決傳統懸吊式液滴培養方式無法持續供給新鮮培養液問題，並能大量增加實驗之通量。我們將液珠形成之物理行為進行理論與實驗分析，在完成液珠形成控制方法之建立後，導入細胞株細胞進行細胞培養與測試。

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