本研究作為主動式微流液珠分選技術(Droplet sorting microfluidics)之優化與延伸，以簡單的電控系統搭配高度靈活性的電極設計，解決此領域的兩大難題：(1)液珠分選的通量極限、(2)複雜的電控系統控制。此研究展示高通量的液珠分選系統，具備三通道、易製作、低成本、非直接接觸電極之優點，展現應用於微流體領域的高度實用性，特別是螢光激發液珠分選系統(Fluorescence active droplet sorter, FADS)及微全分析系統(Micro total analysis system, μTAS)。利用聚焦型流道(Flow-focusing injection)將水珠形成在油中稱為液珠，接著高壓電源供應器施加靜電場於由液態金屬所製作的非接觸式立體電極，液珠在生成時受到電場的影響下產生偏移並流入分選流道中完成分選機制，可有效提升通量限制且避免過於複雜的電極設計與電控系統。實驗數據的測定使用高速攝影機實現對液珠分選機制的影像分析，利用影像處理逐幀分析驗證分選機制並找出不同參數下的液珠生成與電場之間的關係，參數包含液珠通量、大小、型態、軌跡及電場強度。最後，在每秒生成3800顆液珠下實現分選，驗證系統之實用性。

As an improvement and extension of active droplet sorting microfluidics, this study uses a simple electric control system and highly flexible electrode design to overcome two challenges：(1) throughput limitation, (2) complex control system. This research presents a simple, inexpensive, ease to fabricate, non-charged, high-throughput, triple droplet sorter which is highly promising for the droplet-based microfluidic platform and able to benefit for a wide range of applications, especially in fluorescence-activated droplet sorting system (FADS) and micro total analysis system (μTAS). W/O (water in oil) droplets are generated via flow-focusing injection and are deflected into sorting outlets while droplets are forming. Electric field is supplied on the three-dimensional (3D) liquid metal electrodes, which are not in contact with fluid, by high-voltage power supply. This system not only improves sorting throughput significantly but avoids complex electric control. High-speed camera is utilized to record the process of droplets manipulation and data is obtained by image processing software. The relationship between electric field and droplet generation (e.g., throughput, size, morphology, trajectory) is found after analyzing. Finally, droplet sorting at 3800 droplets/s is achieved successfully.

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