利用非線性電滲流開發微型泵與微型濃縮器

The Development of Micro-pumps and Micro-concentrator Using Nonlinear Electro-osmotic Flow

李弘猛(Hung-Meng Lee)

指導教授 ： 王少君

國立中正大學/理學院/化學暨生物化學系/碩士(2013年)

摘要

微流體裝置因為具有可攜帶性且分析的樣品及試劑消耗量少，加上可簡化人工操作，所以有了 lab-on-a-chip 的概念，是現在相當受到重視的領域。但是在微米尺度下，由於晶片管道微小，造成相當大的比表面積，使得流體運作於其上受到摩擦力的作用明顯，利用一般的驅動方式無法有效率地推動流體，及進行微流體的操控。
　　誘導電滲流是指一種利用在可極化表面的誘導電荷產生的電雙層電動滑移現象達成微流體驅動的技術，本篇將討論利用不對稱槽道尖角產生的誘導電滲流作為一個微型泵，探討在流道加蓋以及不同加工方式產生的尖角電滲流速實驗。
　　此外，我們實驗室開發利用奈米孔洞導電離子交換樹酯顆粒在微槽道中，施加一適當電場 (100 V/cm)，作為一個可濃縮溶液中陰離子的為濃縮器．實驗採用螢光染料 FITC (Fluorescein Isothiocyanate)，於濃縮器上進行在不同 pH 值時的濃縮倍率實驗，發現在當 pH 值高於 FITC 的 pKa 時，濃縮倍率隨 pH 值而上升，換而言之，它在較高解離度時有較佳的濃縮倍率，可知受電場牽引後的電泳淌度直接影響濃縮倍率，而且濃縮倍率的對數值與有效電荷數成正比關係。運用此原理也可以於適當 pH 值下，依 pI 值所控制的解離度濃縮胜肽或蛋白質。

關鍵字

微流體 ； 濃縮 ； 電滲流

並列摘要

Because microfluidic devices possess the advantages of portability, low sample and reagent consumption, and simpler manual operations, the concept of Lab-on-a-chip has been a popular research field. However, in the length scale less than micrometer, liquid becomes irrotational and difficult to stir and pump due to small Reynold’s number and large surface force.
Induced electro-osmotic flow is a means using the electrical double layer on the electric polarization surface to drive fluid in micro-devices. This presentation will discuss induced electro-osmosis taking place in the sharp corners at the liquid reservoir to develop micro-pumps. Especially the influences of channel lids and the machining tools creating sharps corners in pumping speeds are investigated.
In addition, our laboratory also developed a micro-concentrator using conducting cation exchange resin granule in a moderate electric field (100 V/cm) as a micro-fluidic device to concentrate anionic species.
In this study, the fluorescent dye FITC (Fluorescein isothiocyanate) was used to study the concentration factor dependence on solute effective charges by controlling the dissociate degrees of FITC in various buffer solutions. One exponential relation of concentration factor versus effective charge was found. This relation leads to develop a selective concentration technique to concentrate ampholyes such as peptides and proteins according to their pI values.

並列關鍵字

electro-osmosis ； concentration ； micro-fluid

參考文獻

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