利用控制微流體系統以提升精蟲篩選之效能

Using Controlled Microfluidic System to Enhance the Sperm Motility Sorting Efficiency

曾新堯(Hsin-Yao Tseng)

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(2013年)

摘要

本論文提出一注射式幫浦(Syringe pump)控制系統佐以微流體晶片，利用流體在微尺度下呈現層流之特性，針對原始濃度及活動力不同的精蟲樣本進行一次性的篩選。運用此技術直接取代傳統篩選方式與人工挑選之過程，同時符合不需離心即可篩選原則以避免可能對精蟲造成的傷害。為證實該系統的精蟲篩選能力，透過流式細胞儀進行實驗分析，結果顯示本研究成功發展出具有篩選精蟲的生醫檢體處理系統。
本研究晶片是經由微機電製程與軟微影技術加工，並選用具備生物相容、低成本、可拋棄式、高精密度及製程簡易等特性之聚二甲基矽氧烷 (Polydimethylsiloxanes, PDMS) 作為實驗基材，相當符合微流體生醫晶片的需求。
人工協助生殖技術(Assisted Reproductive Technology, ART)在醫學領域扮演相當重要的角色，其中，體外受精技術(In Vitro Fertilization, IVF)是將樣本進行前處理，於體外讓一群精蟲與卵細胞自然受精，故精蟲的活動力、總數量等因素將直接影響受精結果。因此可透過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控制微流體系統，主要針對幫浦控制系統與晶片間的連結匹配，其中包含晶片設計、流場模擬、幫浦參數設定以及流式細胞檢測計數的分析結果等。第二階段則延續第一階段的研究，加強篩選效率性與流道設計。從篩選結果可知，活精蟲比例皆可提升至90%以上，濃度與數量上亦有明顯的提升。因此，利用控制微流體系統提供長時間穩定推進之能力與多次設計高效率高穩定度之微流道晶片，成功提升精蟲篩選之效能。最後本論文於第六章提出部分未來可望加以思考的研究方向。

關鍵字

注射式幫浦 ； 層流 ； 精蟲篩選 ； 生醫晶片 ； 體外授精

並列摘要

The thesis presents a controlled microfluidic system which consists of laminar stream-based microchannels. The control microfluidic system is consists of syringe pump and connective tube module. The working concept lies in the microfluidic systems that successfully replace traditional methods, which could select motile sperms without centrifugation steps. Simultaneously, the damage to the sperms could be avoided. The flow cytometric analysis is utilized to confirm the sorting efficiency of this system. The result showed that our study is successfully for sorting sperm.
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.
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 controlled microfluidic system, which focus on the sorting and the classification based on sperm motility and viability. The details including chip design, flow field simulation, pump parameter setup, flow cytometric analysis, and the experiments of semen samples. In the second part, the sorting efficiency and chip redesign were focused to enhance the sorting efficiency in the quality and quantity of sperm. The result show that counted ratio of motile sperm can increase to 90%. Therefore, using controlled microfluidic system is successful to enhance the sperm motility sorting efficiency. At the end, some ideas of future works were proposed.

並列關鍵字

Syringe pump ； Bio-chip ； Sorting sperm ； Laminar flow ； In vitro fertilization

參考文獻

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