改良微流道之設計與參數來加以提升精子篩選效率之成效

TO ENHANCE SPERM MOTILITY SORTING EFFICIENCY BY UTILIZING MICROFLUIDIC CHIP

黃博威(Huang,Po Wei)

指導教授 ： 饒達仁

國立清華大學/工學院/動力機械工程學系/碩士(2015年)

摘要

本論文利用流體在微尺度下呈現層流之特性，藉由此特性去篩選活動力精子，注射式幫浦控制系統有效地提供多個穩定流速使微流體晶片內的不同流體可以呈現出多個不同的層流現象，再利用精子本身的活動力條件，有效突破層流進入儲存槽內收集，以利日後的生醫的醫學應用。
現今醫學上所使用的離心方式需要用快速旋轉的方式使精子分離出來，極大的重力離心條件可能對精蟲造成傷害。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。
由於人工協助生殖技術(Assisted Reproductive Technology, ART)的出現，有助於解決許多不孕的問題存在，在醫學領域扮演相當重要的角色，不管是針對精子注射受精(Intracytoplasmic sperm injection, ICSI)還是體外受精技術(In Vitro Fertilization, IVF)，精子的活動力、總數量、活率等因素將直接影響受精結果，本實驗透過生醫晶片在樣本前處理階段即可篩選出最適合進行人工協助生殖技術的精蟲。
實驗晶片是由微機電製程與軟微影技術加工，並選用聚二甲基矽氧烷 (Polydimethylsiloxanes, PDMS) 作為實驗晶片，他具備幾項優點，如：有生物相容性、低成本、可拋棄式、製程簡易等特性質。
本研究使用微尺度層流現象進而篩選精蟲的控制微流體系統，利用精子的活動力突破層流達到收集的成效。此實驗設計包含晶片設計、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。以緩慢流速提供精子在晶片裡游動的最佳環境，盡可能減少流體對精子游動方向的干擾，最終透過流式細胞儀的幫助，得知收集的精子隻數與比例都有明顯的提升，證實微流道晶片篩選之優勢。

關鍵字

微流體晶片 ； 精子篩選 ； 層流特性 ； 螢光分析 ； 螢光分析

並列摘要

The thesis presents acontrolled microfluidic system which consists of laminar stream-based microchannels. This characteristic is useful for selecting motile sperm.There is some laminar flow phenomenon in chip because flow rate of sperm and buffer are different. Motile sperm has ability to pass through the laminar flow boundary, and reach the reservoir we want to collect.
The bio-chip method is different from traditional methods and centrifugation. Centrifugation need to select sperm by rotating at fast speed, the great gravity maybe will cause the damage to sperm. Finally, the flow cytometric analysis is utilizedto confirm the sorting efficiency of this system. The result showed that our study is successfully for sorting sperm.
Assisted Reproductive Technology (ART) has become an important role in the field of medical science. It provides an important solution to some couple which is suffer from infertility.No matter ICSI (Intracytoplasmic sperm injection) or IVF (in vitro fertilization), sperm motility, quantity, concentration are the main reason for fertilization. Therefore, the optimized microfluidic system provides a perfect opportunity to use an inexpensive requirement to select the most appropriate sperms before IVF process.
The fabrication process of bio-chip include SU8 thick-film photolithography and soft-lithography which is used by PDMS (Polydimethylsiloxanes), which has the advantages of biocompatibility, low-cost, high-precision, disposable, and easy to produce etc., so that it is suitable and common used for biomedical chip.
The study is to construct a microfluidic based controlled microfluidic system, which focus on the sorting and the classification based on sperm motility and viability. The experimental details including chip design, flow field simulation, pump parameter setup, flow cytometric analysis. All parts are a key point associated with the final result.Slow flow rate has favorable environment to increase the opportunity of motile sperm to pass through the laminar flow boundary. Moreover, this environment can reduce interference with direction of sperm swim forward. At the last, more progressive quantity and quality can be observed by the flow cytometric analysis. The result show that counted ratio of motile sperm can increase a lot. Therefore, using controlled microfluidic system is successful to enhance the sperm motility sorting efficiency. It confirms that the microchannel really has an advantage in Assisted Reproductive Technology.

並列關鍵字

Micro-fluidic chip ； Sorting sperm ； Laminar flow ； Fluorescent analysis ； In vitro fertilization

參考文獻

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