本研究以共平面式電極設計一個利用介電濕潤(Electrowetting-on-dielectric,EWOD)驅動方式之數位微流體系統(digital microfluidic system)，期望可應用於微全分析系統(micro total analysis system, μTAS)及實驗室晶片(lab-on-a-chip)。
主要概念是將傳統雙平行板電極結構之參考電極與驅動電極製作於同一平板上，此晶片結構可加入其它功能機制，擁有更彈性之系統發展空間。在無上蓋平板之共平面電極晶片上成功操控微液滴進行來回傳輸以及混合，可操控之微液滴包含脫氧核糖核酸(deoxyribonucleic acid,DNA)、線性選殖載體(linearized cloning vector)、酵素(enzyme)以及磷酸鹽(phosphate-buffered saline,PBS)等緩衝溶液，這樣的晶片結構有更靈活的設計空間。若在上方加上疏水上蓋無電極平板，則可成功操控液滴進行傳輸、合併、分離以及產生動作。
最後，本研究設計核酸接合反應(DNA ligation)系統，在共平面電極晶片上成功完成核酸接合反應，並將完成接合反應之結果與傳統人工進行接合反應之結果進行比較。結果顯示，共平面式電極設計之數位微液滴操控晶片可有效且成功的應用於生物反應實驗上。

This study reports the completion of fundamental fluidic operation considered essential to build digital microfluidic system, which can be used for micro total analysis system (μTAS) or lab-on-a-chip (LOC) by using electrowetting-on-dielectric (EWOD) actuations on coplanar electrodes with no cover plate.
By arranging driving and reference electrodes on one plate, such an EWOD configuration can accommodate more sensing mechanisms from the top, which allows increasing flexibility for system development. Droplet actuation on an open surface with removed top plate is demonstrated, that was shown additional flexibility for the system design. Repeatable transport and mix of microdroplets among DNA, enzyme, PBS and multi-salt reaction buffer to ligate DNA fragment with vector was shown, to establish the compatibility of these fluids with single plate configuration, i.e. no cover plate.
The droplet-manipulation devices is also demonstrated the successful moving, cutting, merging, and creating of droplets in a parallel-plate configuration, i.e. between the driving plat with coplanar electrodes and the other plate with no electrode. Based on the results, single plate configuration EWOD chip could be a novel tool to delivery many kinds of biosamples, such as DNA, enzyme, and salt solution without problem. In this study, we present a success biomolecular ligation procedure by using single plate configuration EWOD chip. The results was shown that single plate configuration EWOD chip can be good enough in the ligation process and the efficiency of ligation was comparable with the one by the conventional practice of pipette.

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