近年來，許多關於微小化的製程技術都已經發展成熟，因此利用微機電技術來對生物分子做操控或分析的研究也逐漸普遍化，也成為生物科技上一項重要領域，主要目的是將所需的功能或是裝置整合至一個實驗室晶片，而且該晶片具有完整的生物檢測或是分析的能力。就以分離細胞的微小化裝置為例，目前已被提出的許多技術如微鑷夾等，都具有一些缺點，因此希望能夠發展出一個既簡單又能有效率地分離細胞晶片。

在這論文中，利用微流體的特性，設計出微流道並配合介電泳的特性以達到具有細胞分離功能的生醫晶片。利用兩道不同流量之微流體匯集，並且使細胞被局限於微流道的壁緣，同時細胞會因為尺寸的差異與阻力的因素產生初步的分離。再藉著施加特定範圍頻率的電壓於所設計的微電極上，對細胞產生負介電泳力，以達到有效的細胞分離與收集的效果。其中先以模擬軟體CFDRC分析與驗證設計概念後，再將整體設計以微機電製程技術完成。實驗過程中以聚苯乙烯之微粒子代替細胞來驗證此生醫晶片的可行性。

Recently, researches about manipulation and analysis of bio-particles by MEMS technology are growing because of the fabrication development, and it is an important field ob bio-technology. The main purpose is to integrate the functions we need into a Lab-On-a-Chip system, and the chips have the function of bio-detection and analysis. Taking the micro-device of cell sorting for example, there are many technology have been presented, such as microgripper. But each of them has some restrications. Therefore, we want to design a bio-chip which could separate cells easily and efficiently.

In this thesis, we use the characteristic of microfluid and design the bio-chip to combine with DEP (dielectrophoresis) and microchannel to sort cells. By collecting the two fluids with different flow rates, all cells will close the wall in the microchannel. At the same time, the cells will separate preliminary because of the sizes of the cells and the drag force. By applying input AC voltage within specific frequency range on the micro electrodes, cells could be separate and collect with negative DEP force. We through numerical simulation software, CFDRC, and the design concepts are realized by MEME fabrication process. At last, we use polystyrene beads in place of cells to demonstrate the functions of our chip.

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