應用整合型微流體晶片系統以提升精蟲篩選之效能

Integrated Microfluidic System for Efficiency Enhancement of Sorting Sperm

傅薈廷(Hui-Ting Fu)

指導教授 ： 饒達仁

國立清華大學/工學院/奈米工程與微系統研究所/碩士(2011年)

https://doi.org/10.6843/NTHU.2011.00349

摘要

本論文提出一整合型微流體晶片系統，已成功的透過微流道晶片所呈現的層流特性，以及符合不需離心即可篩選的原則，直接取代傳統篩選方式與人工挑選之過程，同時避免可能對精蟲造成的傷害，並結合馬克精蟲計數盤與流式細胞儀分析實驗，發展出能夠有效篩選精蟲的生醫晶片。為證實該系統的精蟲篩選能力，進而針對原始濃度及活動力不同的人精及豬精樣本進行一次性的篩選。
本研究晶片採用微機電製程與軟微影技術以聚二甲基矽氧烷 (Polydimethylsiloxanes, PDMS) 作為實驗之基材，其具備生物相容、低成本、可拋棄式、高精密度及製程簡易等特性，並可降低實驗樣本的使用量，相當符合微流體生醫晶片的需求。
以近期生殖醫學技術而言，可藉體外受精技術(In Vitro Fertilization, IVF)進行精蟲樣本之前處理，使部分男性為主因的生育障礙獲得改善，故精蟲的活動力、總數量、濃度等因素將直接影響受精結果。因此，可透過微流道生醫晶片於樣本前處理階段篩選出最適合進行IVF的精蟲。
本實驗研究共分為二階段，第一階段完成一微尺度層流篩選精蟲之晶片系統，主要針對精蟲的活動力進行分析以及探討篩選前後精蟲的死活比，其中包含晶片設計、流場模擬、馬克精蟲計數盤以及流式細胞螢光檢測的分析結果等。第二階段則延續第一階段的研究進一步改良成多重流道之晶片，以探討精蟲篩選率在質與量上的提升。最後本論文於第五章提出部分未來可望加以思考的研究方向。

關鍵字

微流體晶片系統 ； 層流 ； 篩選精蟲

並列摘要

The thesis presents an integrated microfluidic system which consists of laminar stream-based microchannels, makler counting chamber and flow cytometric analysis to enhance the sperm motility sorting efficiency. The working concept lies in the design of multiple channel systems that successfully replace traditional methods, which could be achieved motile sperms without centrifugation steps. Simultaneously, the damage to the sperms could be avoided. The fabrication process of our bio-chip include SU8 thick-film photolithography and soft-lithography, which has the advantages of biocompatibility, low-cost, high-precision, disposable, and easy to produce etc., so that it is suitable for biomedical chip. With the advances in the technologies, reproductive medicine has become an important role in the field of medical science. The main reasons of infertility from male are the abnormality of sperms and the lack of sperms. IVF (in vitro fertilization) technology is a natural in vitro fertilization process that comes after a series of sample pre-treatment. The semen property, including motility, total number, and the concentration of sperms will directly affect the outcome. Therefore, the optimized microfluidic system provides a good opportunity to use and an inexpensive requirement to select the most appropriate sperms before IVF process. The study is divided into two parts. In the first part, the goal is to construct a microfluidic based sperm sorting system, which focus on the sorting and the classification based on sperm motility and viability. The details including chip design, flow field simulation, makler counting, flow cytometric analysis, and the experiments of semen samples. In the second part, the microfluidic system with multiple channels enhances the sorting efficiency in the quality and quantity of sperm. At the end, some ideas of future works were proposed.

參考文獻

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