在眾多腫瘤診斷的技術中，超音波常被使用於臨床醫學診療上，但卻因為缺少適當的影像對比增強劑，無法呈現腫瘤之血管構造，其臨床應用一直無法與電腦斷層或核磁共振掃描相提並論。而以往的超音波對比劑製作，主要是以超音波震盪法來產生，但因為用此法所產生的液珠或氣泡其粒徑分佈較廣，而對於超音波顯像而言，所加入的對比劑尺寸必須與超音波頻率相互搭配才會達到最大效益；若尺寸分佈較大，則較難選擇決定超音波波段用來檢測。
本實驗使用PDMS及PMMA為基材來製作晶片，主要是利用聚焦型微流道製作出以lipid包覆C6F14的微米液珠，由其內包覆液體沸點較低的特性(58℃)，自然於待測物體內受體溫及超音波的影響而氣化形成微氣泡，可減少直接製造微氣泡後因保存不易造成的的不穩定性。本實驗先以便宜的油/水樣本進行效能測試，經過調整多種樣本流率比組合，發現在連續相比分散相流率比值較小的情況下，液珠產生機制不僅由毛細係數控制，亦需加入分散相流率來參考，因而提出針對聚焦型流道的毛細係數相關修正。
另外，實驗時發現若液珠產生區之頸縮處有雜質堵住，則較易產生微小液珠，但因雜質無法控制尺寸及維持再現性，因此我們在液珠產生區內放置固定大小的PS球作為替代。經觀察發現，PS球可有效降低頸縮處之截面積，因而避免製作微小孔洞之困難製程，並可提高液珠產生之穩定性及減小液珠尺寸。最後，使用本裝置搭配可用於活體超音波顯像實驗之lipid溶液和C6F14製作出可真實注入實驗鼠中之微米級液珠，並觀察產生的液珠與毛細係數及兩相流率比間的關係。
關鍵字：微脂質液珠、聚焦型流道、超音波對比劑、毛細係數、雙相流率比。

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