微流體驅動之多功能整合晶片藉由交流電滲流操控微米級樣本

MICROFLUIDIC-DRIVING MULTI-FUNCTION MANIPULATION ARRAY OF MICRO-SCALE BIOLOGICAL SAMPLE VIA AC ELECTROOSMOSIS

趙子佑(Tzu-Yu Chao)

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(2009年)

摘要

A microfluidic-driving array is reported in this paper for the multi-function manipulation of micro-scale biological sample based on the Alternating Current Electro Osmosis Flow, which is achieved by the design of the asymmetric electrode pairs array. The features of our proposed design can not only orient bio-objects but also convey them. The design, simulation and experimental results of this proposed AC electrokinetic manipulation chip are reported in this paper. The microfluidic-driving manipulation array is consisted of titanium electrodes layer and SiO2 dielectric layer on top, but the functional electrodes are exposed without the dielectric layer. The manipulation electrodes are composed of the asymmetric-pairs electrodes arranged in line and circle. All of them are embedded in the device chamber. The functional electrodes are driven by using a waveform generator that provides the sinusoidal wave excitation of 2 to 10 volts peak to peak. When the ac potentials are applied to these asymmetric electrodes, a uni-direction flow can be generated by the gradient of the electric field. Responding to the frequency of ac potentials applied, the net electroosmosis flow is induced to different direction that results from both capacity charging and faradic charging effects. Then, the bio-particles can be driven with the electroosmosis flow, be orient to the near functional electrodes, and conveyed. According to the design of our circularly arranged electrodes, the inside width of electrodes is smaller than the outside width. The flow velocity increases with the decrease of the electrode dimensions, while we keep the same ratios between the electrode widths. By the control of voltage and frequency applied to manipulation electrodes, the manipulation features of the microfluidic-driven bio-particles can be used for various applications. In this paper, we use micro-spheres (latex beads) of 8μm, which has the similar size to cells, as target objects and 50μM NaCl water solution as the experimental medium to demonstrate the manipulation functions.

關鍵字

微流體驅動 ； 電滲流 ； 不對稱電極對 ； 圓形排列電極 ； 電容效應 ； 法拉第效應 ； 乳膠微粒子

並列摘要

一個微流體驅動之多功能操控陣列晶片使用交流電滲流來操控微米級生物樣本，藉由不對稱電極對的設計來達到驅動的效果。我們所設計的電極陣列不只能導引生物性目標物，更能輸送操控它到我們想要的地方。這裡所提出來的交流電動力操控晶片設計之模擬與實驗結果也在此篇論文中做討論。微流體驅動之操控陣列是由鈦金屬電極層以及氧化矽絕緣層所組成，而具有驅動能力的電極在微流道中沒有絕緣層覆蓋。整個操控陣列是由不對稱電極對以直線與圓形排列而成。且整體被包含在一個微流道腔室當中。驅動電極的交流電訊號源是使用波形產生器所提供，產生二到十伏特波峰對波峰的正弦波。當交流電訊號施加在不對稱電極上時，一個具有相同方向的流體被不對稱的電場所驅動出來。調控所施加的電訊號頻率，由於電容效應以及法拉第效應所造成的結果可使電滲流產生不同方向的靜流量。接著，所要操控的生物性樣本就會被電滲流所驅動，它們會被引導到啟動的電極上，並且被輸送到設定的標的位置。各種以微流體操控生物性樣本的方式可被應用在各種不同方面的研究。在這篇論文中，我們使用八微米的乳膠微粒子當作我們的操控目標物，大小近似於細胞等級，並以五十微莫耳的氯化鈉水溶液當作實驗液體，來呈現整個操控晶片的性能。

並列關鍵字

microfluidic-driving ； electroosmosis ； asymmetric electrodes pairs ； circularly arranged electrodes ； capacity charging ； faradic charging ； latex beads

參考文獻

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