利用介電泳力捕捉單顆細胞之微晶片設計

A Microchip Design for Single-Cell Trapping by Dielectrophoresis Force

宋建緯(Chien-Wei Sung)

指導教授 ： 劉承賢

國立清華大學/工學院/動力機械工程學系/碩士(2008年)

摘要

近年來，在單細胞操控晶片不斷的發展下,許多操控生物分子的方法被研究學者們所提出，，但是大多數的方法有其限制與缺點。其中利用交流電動力學的方法來操控生物分子具有大量、快速且對生物分子無傷害的優點。而根據電動力學理論，當施加一交流電場時，可使其中可極化粒子產生出一與頻率相關的電雙極，藉由與周圍介質在非均勻電場下交互作用，可產生介電泳(dielectrophoresis)現象，而介電泳現像就是最常用來操控生物分子的方法。
在本論文中，我們提出一個新的單細胞補捉晶片，並利用介電泳現像來進行補捉。為了要達到補捉單顆細胞的目的，所以在此微晶片中設計了兩個補捉機制。首先利用正介電泳力將細胞集中在每個電極上，接著，藉由調整交流電的頻率而使細胞受到負介電泳力作用。因此，在電場較弱區域的細胞將會分別地被補捉住，而達到單顆細胞補捉的目的。我們利用CFDRC模擬軟體來驗證晶片的設計概念。在實驗中我們利用了乳膠粒子與人類血癌細胞株(HL-60)來當作捕捉的對像。而實驗結果顯示，補捉的特性取決於交流電的頻率和補捉物的特性。藉由調整適當的頻率，我們成功地補捉了單顆細胞。

關鍵字

操控 ； 介電泳 ； 單顆細胞捕捉 ； 電動力學

並列摘要

In recent years, continuous achievements have been made on the research and development of the microchip for single-cell manipulation. Therefore, many methods for manipulations of bio-particles have been proposed, but most of proposed methods have some limitations and disadvantages. Hence the AC electrokinetic technologies have been developed and provided more effective for manipulations of bio-particles without harm. The term AC electrokinetics refers to the movement of particles using AC electric fields. An AC electric field induces a frequency-dependent dipole on a polarizable particle. The interaction between the dipole and the non-uniform electric field is such that the particle experiences a force. This effect is called dielectrophoresis (DEP) which is the common method for the manipulation of bio-particles.
In this thesis we present a novel microfabricated dielectrophoretic trap designed to trap single cells. The design of our microchip consists of two mechanisms in order to reach the goal of single-cell trapping. First, cells accumulate on each microelectrode due to positive DEP force. Second, single cells are trapped individually in the region of minimum electric-field intensity due to negative DEP force. By utilizing the CFDRC simulation software, we validated the feasibility of the design concept. For the experiments, we used the latex bead and the HL-60 cell line as our trapped objects. The experiment results show that the trapping characteristic is dependent on frequency of the applied AC electric field and the properties of the trapped object. However the single-cell trapping has been demonstrated successfully through the experiments by tuning at the appropriate frequency of the applied AC electric field.

並列關鍵字

manipulation ； dielectrophoresis (DEP) ； single cell ； AC electrokinetics

參考文獻

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