Cell Separation In Microfluidic Channels

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2013Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2013Bu çalışmada yaklaşık 15 mikron çapında olan MDA-MB-231 ve yaklaşık 20 micron çapında olan MCF7 insan meme kanseri hücreleri içeren karışımdan MCF7 konsantrasyonu için Dean akışından faydalanan dönel kanal tasarımı yapılmıştır. Buna göre dört farklı yükseklik x genişlik değerlerine sahip olan kanallar üretilmiştir. Bu kanallar, bir giriş ve üç çıkışa sahiplerdir. Hedef hücre olan MCF7 hücre iki farklı floresan boya ile boyanmış ve öncelikle bu boyaların hücrelerin yüzde kaçında etkili olduğunu belirlemek için akış sitometrisi ile analiz edilmiştir. Bu analizden sonra ilk önce dizilim için uygun debileri bulmak üzere deney kurulmuş ve boyalı MCF7 hücreleri ve boyanmamış MDA-MB-231 hücreleri her birinden 100 ml’de bir milyon olacak şekilde toplam iki milyon hücre içeren karışım hazırlanmıştır. Bu karışımdan her bir kanal için 20’şer ml alınarak deneyler gerçekleştirilmiştir. Bu deneyler sırasında yüksek debilerde çalışılması gerektiği anlaşılmıştır. deneylere göre gerekli debiye ulaşıldığında kanalların 2. çıkışlarında MCF7 hücreleri dizilimi olduğu görülmüş ve bu akış sitometrisi analizi ile de doğrulanmıştır. İkinci yapılan deneylerde MCF7 hücreleri ilkinden farklı bir boyayla boyanmıştır ve daha fazla sayıda debi incelenmiştir. Üretilen dönel kanallar, ucuz ve küçük boyutlu, hızlı ve daha doğru sonuç alınabilecek bir teşhis cihazı geliştirmede ön çalışma olarak kullanılabilecek bir tasarım olmuştur.In this work, Dean force coupled curved microchannels were designed for concentration of MCF7 human breast cancer cells from a suspension that contains MDA-MB-231 (~ 15 μm in diameter) and MCF7 (~ 20 μm in diameter) human breast cancer cell lines. Channels which have four different height x width dimensions were fabricated. Channels had one inlet and three outlets. Target cell –MCF7- has stained with two different fluorescent dye and effectiveness of these dyes were investigated with flow cytometry. Experiments were performed to determined apoppriate flow rates for focusing. Then, a million labeled MCF7 and a million unlabeled MDA-MB-231 cells were mixed in 100 ml solution. 20 ml cell suspension was used for each experiment. It was understood that high flow rates are required for focusing of MCF7 cells and according to first experiment there was MCF cell focusing at second outlets . Experiments showed that MCF7 enrichment at the second outlets of each channel and it was confirmed with flow cytometry analysis. Then another group of MCF7 cells were stained with another fluorescent dye for second experimental group and more flow rate values were investigated. These curved channels can be regarded as a prototype of a microfluidic diagnostic device with their fast reaction time, relatively accurate results, cost effective and miniaturized features.Yüksek LisansM.Sc

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