介電泳場流分離法(DEP Field-Flow Fractionation , DEP-FFF)是一種結合介電泳力與流體力兩種力的細胞分離法，使不同介電性質粒子受介電泳力作用漂浮到流場中不同高度，進而利用流場內速度不同而分離細胞。本研究主要是以微機電製程加工技術(MEMS fabrication)於玻璃基底上製作指叉型電極(Interdigitated microelectrodes)，並利用其不均勻電場(Nonuniform electric field)，使粒子受負介電泳力作用而漂浮。根據介電泳力與其粒子所受重力平衡條件，利用解析方法推導出粒子漂浮高度近似解，同時使用數值模擬方法計算出粒子漂浮高度，與解析近似解相比較。
　　本研究觀測的生物粒子具有滲透壓的性質，實驗的流體必須使用“等張溶液”，不同的等張溶液，導電性介電性也有所不同，將探討等張溶液對於粒子聚焦與粒子漂浮高度的影響與一些實驗問題的解決方法。

In this study, MEMS-fabricated interdigitated microelectrodes were used to generate the non-uniform electric fields. So the particles floating by the negative DEP force. By taking advantage of dielectrophoretic (DEP) and hydrodynamic forces, DEP Field-Flow Fractionation (FFF) technique is firstly used DEP force to levitate particles to different heights according to their different dielectric properties. Based on the parabolic velocity profile of channel flow field, particles could be separated by height or velocity difference.
This study used RBCs. RBCs will affect by osmotic pressure. So the fluid must be used "Isotonic solution". Isotonic solution is an important experimental parameter. If the Isotonic solution is different, they will have different electrical conductivity and dielectric. To investigate the impact of difference isotonic solution for blood cells focusing and levitation heights. And solve some experimental problems.

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