本研究利用液滴微流體晶片，同時讓液滴分別包覆兩種不同的微粒，並讓兩液滴在交會處進行一對一碰撞合併，達到產生包覆成對微粒的液滴的目的，其能建立包覆成對微粒的平台。液滴微流體已廣泛運用於生物應用上，一個微小液滴即為一個獨立的微反應器，每個包覆在液滴內的物質可不受外界的影響，讓液滴內的生化反應運用在各項用途。相較於傳統方法，液滴微流體可大幅縮短操作時間、步驟及反應所需的材料量。
研究結果顯示，最終包覆雙顆成對微粒的效率與單微粒的包覆效率有關，此與液滴大小、流道設計、微粒懸浮液濃度、流率調控等亦有極大的關聯性。當流體之總流率越大或是連續相與分散相的流率比值越大，則產生的液滴大小就會越小。使用close-packed設計的流道，連續相和分散相流率為0.16ml/hr和0.04ml/hr下，包覆10µm單顆粒子效率為40%，而包覆雙顆成對微粒的效率為21%，為了減少粒子沉降的問題，我們使用密度與粒子相近之蔗糖溶液作為分散相，可以提升包覆10µm和20µm單微粒的效率分別達到68%和65%，而包覆單微粒的兩液滴經過一對一的碰撞合併後，最終一個液滴包覆一顆10µm和一顆20µm的微粒效率為38%。
關鍵字：液滴微流體晶片、微粒包覆、液滴配對、液滴合併、正16烷

Droplet-based microfluidics have been used in biological applications widely. Each micro-droplet is an independent micro-reactor and the material inside the droplet is not affected by the environment. Compared with traditional methods, droplet-based microfluidics can decrease the operation time, steps and the amount of materials required substantially. In this study, the droplet-based microfluidic chip was used to encapsulate paired particles by coalescing two droplets with single particle individually at the channel intersection.
The results showed that the efficiency of encapsulation of paired particles was related to that of single particles, which depended on droplet size, channel design, particle suspension concentration, and flow rate. Using the close-packed channel design at the flow rate of continuous and dispersed phase 0.16ml/hr and 0.04ml/hr, respectively, the encapsulated efficiency of 10μm single particle was 40%, which led to the encapsulated efficiency of paired particles 21%. When using the sucrose solution with density similar to the particles as the dispersed phase, sedimentation of particles was alleviated and the encapsulated efficiency of 10μm and 20μm single particles was 68% and 65%, respectively. This resulted in encapsulated efficiency of paired particles was 38%, relatively efficient compared to those in the literature.
Key words: droplet-based microfluidics, particle encapsulation, droplet pairing, droplet coalescence, n-hexadecane

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