- 學位論文
以負壓驅動之微流道耦合系統
Coupled Mixing and Focusing Flow Studies for a Unified Vacuum-pumped Microfluidic Device
摘要
微流體系統具備流體混合、反應器、輸送、分離和生物樣品檢測等多種功能的特點，並可將前列功能整合於單一微晶片系統上，以應用於生物化學，生物醫學領域中。本研究提出以真空幫浦為驅動源之整合型微流體裝置，其組成部分包含微流體混合器模組與流式細胞儀模組。研究目的在達成連續不間斷的流體混合與水力聚焦過程，以實現快速篩選標靶細胞的檢測。在前段的模組元件，我們採用良好混合性能的二維被動式特斯拉構型；後段模組則配置一微流式細胞儀，以矩形十字微流道實現二維對稱之水力聚焦。利用混合與水力聚焦之耦合數值分析，以預測該併合微流晶片的吸力驅動之流場行為，並利用光微影技術，以SU-8光阻進行黃光製程與PDMS翻模構型製備此微流體裝置。數值模擬與實驗分析結果皆證明，此研究之微流體裝置成功的達成93%的混合效率以及聚焦流體寬度被縮減於18μm。
並列摘要
Microfluidic devices holding multi-functional elements have been a highly promising tool to implement mixing, reaction, transport, separation, and detection of bio-samples on a solitary microchip for diverse applications in the biochemistry, biophysics and medical fields. This work presents a unified vacuum-pumped microfluidic device which consists of a micromixer module and a microflow cytometer module to achieve a continuous sequence of mixing and hydrodynamic focusing procedures for possible rapid screening of the marker cell detection. For the former module, an in-plane passive micromixer with optimum Tesla structures was adopted to achieve good mixing performance. We also devised a microcytometer as the latter module to attain planar symmetric hydrodynamic focusing in rectangular microchannels. Using the coupled mixing and hydrodynamic focusing analysis to predict the suction-driven flow behavior for guiding the chip design, the microfluidic device was fabricated via SU-8 lithography and a PDMS replica molding technique to construct reverse structures from the patterned SU-8 molds on a silicon substrate. Numerical and experimental results have demonstrated the capability of the developed microfluidic device to realize a 93% mixing index and to control the focused stream within a width of 18 μm in tests.