本研究為發展一種可調式介電泳微流系統，用於分離微小、不同尺寸的粒子，並希望能將本裝置應用在生物粒子，如:微胞、血球的分離上。與以往許多藉由介電泳力分離粒子的裝置相比，本研究將L型形狀電極與微流道中出口流道的相對位置技巧性的排列，利用流道壁面攔截粒子進行分離，因此能大幅降低所需的流道長度與電極數目，使能分離的粒子大小差距減少，且增加能同時分離粒子的尺度數目。在本實驗中，1, 3, 5 μm的乳膠粒子已成功在不超過 1毫米的流道中被分離，並透過調控電壓和輸入流率的比例，可即時改變欲分離粒子的大小並得到理想的分離結果，使得本裝置具備高耐用和靈活度。最佳化的分離效果是將這三種不同尺寸的粒子分別排序在不同的出口流道中，各有 92.7 %, 75.2 % 以及94.3 %的比率。透過模擬與實驗結果的相互對照，已驗證裝置可以快速、自動化與高通量同時分離粒子的可行性。最終希望將本技術應用到生物粒子的分離，在未來得以和生物醫學結合，具有開發定點照護晶片之潛力。

This research develops a tunable size-based microfluidic system by using the force of negative dielectrophoresis (nDEP). A sample stream containing a mixture of particles is pinched in the upstream and then sorted by size after flowing over planar interdigitated electrodes. The L-shaped electrodes and flow chamber were aligned in a particular arrangement to yield an optimal sorting effect. 1, 3, and 5 µm polystyrene (PS) particles were successfully separated into three distinct streams in a short distance (1 mm) and collected in different outlet channels. The sorting could be modulated by flow rate and electric potential. The optimal experimental sorting efficiencies of 1, 3, and 5 µm particles achieved 92.7 %, 75.2 %, and 94.3 %, respectively. Based on the principle, further sorting of smaller particles is achievable.

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