生物細胞的操控與檢測在生醫應用中是非常重要且不可或缺的。為了避免破壞及影響細胞，本論文使用非接觸式的介電泳力來分離細胞，利用導電溶液中絕緣式結構壓縮電力線產生不均勻電場，使生物粒子因受介電泳力的影響，驅動往高電場密度或低電場密度區域移動，利用正介電泳力捕捉死細胞於流速低之高電場梯度區域，負介電泳力會驅逐活細胞至流速高之低電場梯度區域，以控制方式來達到死細胞與活細胞的分離，並能在出口產生不同粒子之分離及收集。本文利用數值模擬分析設計絕緣式介電泳晶片(iDEP)之X型結構進行電力線壓縮，更改結構間距及角度找出最佳化設計並依此設計做實驗驗證模擬結果，針對不同流速及電壓操控可以有效分離生物細胞。
此外，以該絕緣式介電泳晶片為基礎，發展非接觸電極施加方式，以20 m寬之PDMS區別流道及插入電極之高導電度溶液儲存槽，設計了非接觸絕緣式介電泳晶片(cDEP)，該微型晶片可有效聚焦乳膠粒子，乳膠粒子受負介電泳力排斥會趨向流道中心，輔以流體力可快速壓縮聚焦乳膠粒子。數值模擬與實驗結果皆表明，在高電壓、高頻率、低流速都可以增加聚焦效率。
近來可有效隔離稀有的循環腫瘤細胞(circulating tumor cells ,CTC)之裝置對於醫療診斷是十分重要的。本文中使用之非接觸絕緣式介電泳晶片可有效的區別HeLa 細胞及紅血球細胞，主要利用HeLa細胞可產生較紅血球細胞多於七倍之介電泳力。依此介電泳力大小之差異性可利用不同電壓及流速提高分離兩種細胞之效率。

Manipulation and discrimination of biological cells is essential to many biomedical applications. Insulator-based dielectrophoresis (iDEP) trapping consists of insulating structures which squeeze the electric field in a conductive solution to create a non-uniform electric field. Cells with different dielectrophoretic responses were therefore separated and collected in the outlet. Simulations were numerically performed to investigate parameters of the design in the present study. Furthermore, experiments were also conducted to demonstrate the feasibility of hydrodynamic separation using iDEP in the proposed design. The main purpose of the present study was to investigate the feasibility of applying the technique of contactless dielectrophoresis (cDEP) on an iDEP micro-device with effective focusing of particles. The latex particles were, therefore, repelled toward the center of the micro-channel by the negative dielectrophoretic forces generated by the insulating structures. The numerical simulations and experimental results indicated that an increase in the strength of the applied electric field significantly enhanced the performance of focusing. The ability to isolate rare cells, such as circulating tumor cells (CTC), is important for medical diagnostics and characterization. The cDEP device can effectively isolate HeLa cells from a peripheral blood sample. The magnitude of the dielectrophoresis force acting on HeLa cells is about seven-fold that on red blood cells (RBCs) under a given electric field distribution in a sucrose medium, making it possible to separate HeLa cells from normal blood cells.

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