以微流體技術製備微液滴的研究已發展多年，在此系統可進行多種程序操作如：混合、反應、分離等，因此微液滴可做為微小反應器，提供獨立操作的環境進行各種化學反應以及生物分子偵測。
螢光染色法為最常使用的生物分子偵測方式之一，在微流體系統中整合螢光偵測所需各程序的研究正快速發展中，但因染劑常吸附於流道表面上，造成高螢光背景值，使得偵測效果極差，在本研究中第一部分裡，藉由微液滴系統進行降低螢光背景之偵測，以微液滴作為偵測區域，利用疏水性連續相與疏水性染劑高親和力之特性，萃取出液滴中未標定於生物分子上之染劑，降低液滴內偵測區域之螢光背景值。研究中將染劑與細胞脂質包覆在液滴中做染色標定，觀察此系統降低螢光背景值之效能。此系統下，分別在小球藻實驗與NIH/3T3實驗中減少了85%及58%的螢光背景值，螢光偵測細胞脂質之訊雜比在小球藻實驗中增加17倍，NIH/3T3實驗中增加10倍。
除了進行生物分子偵測外，以微流道系統製備微粒子作為載體的研究在目前也備受注目，在此系統下可準確的控制實驗參數，並製備尺寸及型態均一的微粒子。本研究第二部分中首先利用成本較低及製備簡便的褐藻酸鈉，作為製備粒子之材料，研究不同微流道系統設計以及不同操作參數對於微液滴與微粒子製備之影響。
在液滴產生方面，流道的設計採取T字形交界處形成液滴的方式，與Y字形流道比較，T型流道中的分散相受兩流體間的剪切力較大，分散相比較容易產生液滴，液滴生成的時候也比較穩定。液滴生成之尺寸與毛細係數、相對流量、相對黏度有關，液滴尺寸隨著相對流量的增加而增加，當毛細係數增加時，液滴尺寸隨之減小。而提高分散相黏度時，生成之液滴較小，其原因推測為較高濃度的褐藻酸鈉溶液之黏度相對較大，在產生液滴時因黏滯力較大，分散相溶液補充形成分散相前端的速度較慢，所以產生直徑較小的液滴。在使用不同濃度（黏度）的褐藻酸鈉時，會隨著褐藻酸鈉濃度（黏度）越高，生成的粒子形狀越完整，粒子的膠體強度也比較強。因此可依不同的情況選擇不同的粒子膠體強度，做適當的運用。
了解製備微粒子之操作機制後，在本研究第三部分，選擇較特殊的材料－導電性高分子，做為進一步的應用。以此材料可成功的包覆具有產電活性之細菌在微粒子之中，並在檢測裝置中進行培養，觀察粒子中所包覆之微生物是否有產電潛力。藉由導電性高分子包覆微生物作為細胞培養載體以及三維電極，可增加收集電流之面積，有利於快速篩選產電微生物，作為微生物燃料電池之應用。

The studies of manipulating micordroplets by microfluidics have been developed for many years. Microfluidic droplets can integrate multiple processes such as mixing, reaction, analysis and detection. Digital microfluidic systems, or microfluidic droplets, serve as microreactors and provide independent environments to conduct chemical reactions and biomolecule detections.
Fluorescence is one of the most used methods for detecting biomolecules. And the integrated processes of fluorescence detection in microfluidics have been extensively studied. However, hydrophobic and autofluorescent dyes can cause high fluorescence background, resulting low signal to noise ratio in the microchannel.
The first par of this study demonstrates an integrated process including cell labelling, fluorescence background reduction, and biomolecule detection using liquid-liquid extraction in the microfluidic droplet system. The cellular lipids in Chlorella vulgaris and NIH/3T3 cells were labelled with a hydrophobic dye, Nile red, to investigate the performance of the proposed method. The fluorescence background of the lipid detection can be reduced by 85%. Removing Nile red increased the signal to noise ratio to 22 and 34 for Chlorella vulgaris and NIH/3T3, respectively, and these were 17 folds and 10 folds of the values before extraction. The proposed method successfully demonstrates the enhancement of fluorescence detections of cellular lipids and has great potential in improving other fluorescence-based detections in microfluidic systems.
The studies of producing microparticles in microfluidic channels have also attracted intense interest recently. The discreteness enables the accurate control over the experimental parameters within individual droplets. In the part 2 of this study, we used alginate which is inexpensive and easy to prepare to investigate the experimental parameters for fabricating microparticles. Among T-junction and Y-junction, alginate and CaCl2 microdroplets were formed stably at the T-junction. However, it was difficult to achieve the production of monodispersed droplets at the Y-junction because of the weaker shear stress provided by the continuous phase. The size of microdroplets was controlled by the capillary number, relative flow rate and relative viscosity between two phases. When capillary number increased, droplet size decreased. The droplet size also decreased when the viscosity of dispersed phase increased. The concentration/viscosity of the sodium alginate solution affected the rigidity of Ca-alginate microparticles. The microparticles fabricated with higher concentration of alginate maintained their shapes after the gelation and the gel structure of alginate was more rigid. Different gel structures can be fabricated for desired applications.
After understanding the mechanism of manipulating microparticles, we chose conductive polymers as the material for application in the part 3 of this study. We successfully encapsule microbes in the conductive microparticles. Conductive microparticles as the 3D cell carriers and electrodes provide enormous surface area for electron transfer. The detection system is designed to monitor the electricity generation from microorganisms encapsulated in microparticles made of conductive polymers to screen electroacive microbes for application in microbial fuel cells.

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