運用離心微流體平台於方波型微混合器之設計與分析

Design and Analysis of Square-wave Micromixer on Centrifugal Microfluidic Platform

李懿修(Yi – Siou Li)

指導教授 ： 郭如男

國立虎尾科技大學/工程學院/自動化工程研究所/碩士(2015年)

https://doi.org/10.6827/NFU.2015.00010

摘要

本研究是針對改變幾何形狀與不同入口角度來設計數種方波型微混合器於離心平台上執行血漿混合功能，並利用數值分析達到設計最佳化與減少實驗成本之目標。微混合器主要分為二合一、三合一及三合一三維方波型混合器三種類型，當微混合器在旋轉平台上會因離心力與柯氏力作用推動血漿與試劑於緩衝槽做第一次衝擊混合，及在方波型流道轉角處增加渦流效果以提升混合效率。在設計過程中先以多重物理量耦合軟體(COMSOL)進行流場模擬，以達最佳化方波型微混合器設計之目的。晶片以微機電製程技術與雕刻機兩種方式先製作出母模，再以高分子材料(PDMS)進行翻模，之後再利用氧電漿改質方式進行接合完成微流體晶片。實驗以 DI water 與血漿進行混合驗證模擬結果，實驗結果顯示以三維混合器最佳可在離心平台 1000 rpm 下 5 秒內達 91.4%混合效率。此微流體晶片實際生醫檢測則執行凝血酶原時間之量測，其 20 次血漿樣本量測結果平均凝固時間為 11.4 秒F。本研究單次檢測全程時間包含樣本導入、血漿混合及量測凝血酶原時間約為 45 秒，可提供一套快速低成本且高效率的離心微流體系統在生醫檢測之應用。

關鍵字

離心平台 ； 微混合器 ； 離心力 ； 柯氏力 ； 凝血酶原時間

並列摘要

This study focuses on changing geometrical shapes and different inlet angles to design a variety of square-wave micromixers for mixing blood plasma on a centrifugal microfluidic platform and achieve optimal results through numerical analysis, thus reducing the cost of the experiment. Micromixers can generally be divided into 21, 31 and 31 3D square-wave mixers. Micromixers on rotating platforms propel blood plasma and reagent in the buffer reservoir to perform the first stir mixing under centrifugal force and Coriolis force, and increasing the vortex effect at the corner of square-wave channel, as well as improving mixing efficiency. During the design process, finite element software (COMSOL) is first applied to simulate the flow field and determine the optimal square-wave micromixer. The microfluidic mixers were fabricated using both conventional soft lithography techniques and CNC machining process. The experimental results show that a mixing efficiency of up to 91.4% can be achieved within 5 s when using a 3D mixer on a centrifugal platform under 1,000 rpm. The feasibility of the proposed device for clinical applications has been demonstrated by performing prothrombin time (PT) tests using plasma samples obtained from 20 healthy male donors, the mean time required for coagulation was determined to be approximately 11.4 s. It is shown that the mean time required to complete the entire PT test (including loading, mixing and coagulation) is less than 45 s.

並列關鍵字

Centrifugal microfluidic platform ； Micromixer ； Centrifugal force ； Coriolis effect ； Prothrombin Time

參考文獻

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