本文利用電驅動流體的方式，以操控樣品之流動及樣品之混合，作為生物分析的應用研究。晶片的製造採用常見的微影和化學蝕刻過程，再以高溫熔融的方式結合晶片。本文分為兩大部分：第一部分稱為微流體進樣晶片、第二部分稱為微流體混合晶片。
　　微流體進樣晶片中，我們設計一個單一微流體進樣晶片(1×N微流體進樣晶片)，利用不同的電壓控制，驅使單一樣品流到不同出口槽。再將其觀念擴展到多個入口槽與出口槽(M×N微流體進樣晶片)，做更多不同的操控。實驗結果指出，樣品流皆能以電動力驅動，再經由側邊管道的集中，引導至所要求的出口槽，並成功的減少電壓控制的操作點。
　　微流體混合晶片中，我們設計兩種不同的混合方式，第一種利用交流電與直流電場的交互作用，試著改變流場的流動狀態驅使液體產生混合。實驗結果指出，使用交流、直流電場所產生的混合效果並不顯著，液體間大部份依靠擴散效應混合。第二種則是在入口兩端加入不同電導濃度的液體，並施加一定的電場強度，使其產生電動不穩定的現象來混合液體。實驗結果指出，利用電動不穩定現象的混合效果佳，並可大幅減少混合區域的長度，而液體間的混合依靠對流及擴散效應。

　This study presents experimental investigations into electrokinetic focusing flow injection and electrokinetic flow mixing for bio-analytical applications. Microfluidic chips were fabricated in glass substrates using conventional photolithographic and chemical etching process, and then the chip was bonded via a high-temperature fusion method.
　For electrokinetic focusing injection technique, we design a novel single microfluidic device possesses two injection techniques for microfluidic sample handing. Therefore, the device not only control single sample flows into different outlet considered in the current operational condition but also the multi-sample injection into specific outlet ports. The experimental results indicated that the sample flow could be electrokintcally pre-focusing to a narrow stream and then guided into a desired outlet port and successfully reduced control devices of the voltage in the microfluidic chip.
　Furthermore, electrokinetic micro-mixing was also investigated in the current study. First, AC sinusoidal electric field perturbation enhanced electrokinetic flow mixing in a T-type microfluidic chip was presented. Experimental results indicated the mixing efficiency increased insignificantly using AC electric field. Second, electrokinetic flows with electrical conductivity gradient in a T-type channel under DC electric field was investigated and used to enhance the electrokinetic mixing in microchannels. When the electrical conductivity gradient exists in the bulk fluid, there is net charge density in the bulk liquid away from electrical double layer (EDL). As the electric field strength achieves the critical value, the flow field is unstable and chaotic. Therefore, the mixing efficiency can be enhanced significantly under this mechanism.
　Finally, the microfluidic chips presented within this study possess an exciting potential for use in a variety of techniques, including high-throughput chemical analysis, cell fusion, fraction collection, fast sample mixing, and many other applications within the micro-total-analysis systems field.

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