開放式循環腫瘤細胞濃縮收集晶片之研製

Study On the Open-Top Microreservoir for CTCs Isolation

吳信輝(Hsin-Hui Wu)

指導教授 ： 任春平

國立中正大學/工學院/機械工程學系/碩士(2013年)

摘要

癌症病患在癌細胞轉移發生初期，循環腫瘤細胞會轉移至身體各重要器官，如能早期檢測體內血液之稀少癌細胞，可降低死亡率。而進行循環腫瘤細胞檢測，須先將癌細胞從血液中分離或濃縮，而過去濃縮細胞方式需要使用大型儀器，且在大樣本量下進行，不利於個人醫療檢測。本研究目的主要是在不破壞細胞之前提下且無需外加微幫浦及電源訊號產生器，製作手持式裝置針對全血樣本進行分離癌細胞與紅血球細胞，利用稀少細胞與紅血球不同的臨界電壓的驅動特性，進行濃縮與分離。因此設計及製作一大面積圓形平面電極之細胞濃縮晶片，以步進式電場切換的動作，利用兩相鄰電極上施加的電壓使兩電極間距產生強電場區域，正介電泳會使細胞朝向位於兩電極間強電場的方向移動，以達到同時驅動及濃縮細胞之目的。於研究中也將使用商用計算流體力學軟體CFD-ACE+來模擬電場強度之變化趨勢，於實驗中先以子宮頸癌細胞進行實驗測試，分別施加15 V向外及10 V向內之步進電場且頻率為1 MHz，成功將紅血球細胞分離於外圈電極，而子宮頸癌細胞則濃縮至內圈電極部分。此外，本研究亦加入紅血球裂解液，輔助進行乳癌循環腫瘤細胞之濃縮，只需要8 V向內之步進電場即可達到濃縮乳癌循環腫瘤細胞之目的。

關鍵字

循環腫瘤細胞 ； 細胞分離 ； 微流體晶片 ； 介電泳 ； 稀少細胞

並列摘要

The detection of rare cells, such as circulating tumor cells (CTCs), circulating fetal cells, and stem cells, is important for medical diagnostics and characterization. The present study develops a handheld electric module which provides stepping electric fields for dielectrophoresis (DEP) to selectively concentrate CTCs from red blood cells, making it low-cost and automated. The circular microelectrodes were designed to generate a stepping electric field by a handheld electric module with a voltage-frequency converter and an operational amplifier. The transparent electrodes were fabricated by patterning the indium tin oxide (ITO) coated glass to observe the experimental results apparently. The large volume open-top cistern for 100 μL was employed to replace conventional microchannel. Positive dielectrophoretic cells were guided toward the center of the microchamber due to the movement of the high-electric-field region. The magnitude of the DEP force acting on HeLa cells is about seven-fold that acting on red blood cells under a given electric field distribution, making it possible to separate HeLa cells from normal blood cells without any hydrodynamic force. The concentrations of HeLa cells for 500 cells/mL were selectively concentrated. The voltages for outward and inward stepping electric field were 15 Vpp and 10 Vpp respectively at a frequency of 1 MHz. Besides, the RBC lysis buffer was employed to concentrate the CTCs of MCF-7 in this study. Experiment results demonstrate the MCF-7 cells also can be concentrated by the open-top concentrate chip.

並列關鍵字

dielectrophoresis ； circulating tumor cells ； cellular concentration ； microfluidic chip ； rare cells

參考文獻

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