本研究提出一種以影像偵測為基礎的新式微型多管道流式細胞儀，免除細胞染色及各種精密光學檢測儀器之使用，可進行細胞之計數及分離。以多管道設計結合流體分流之概念，將邊鞘流體進量口由四個縮減為一個，減少測試儀器之使用量、節省晶片製作及封裝測試時間。利用水力集中效應將樣品流聚焦，配合顯微鏡及灰階高速數位攝影機對晶片管道進行拍攝，以影像軟體計算不同尺寸之粒子數目及速度。在晶片管道末端設計三個流體出口，並利用負介電泳力進行細胞分類及蒐集。

　　使用螢光標定之細胞計數方法，過程十分繁雜，而且一次僅能對一條樣品流進行偵測，本研究針對此點，使用影像偵測方法，對細胞進行計數，計數過程不需對細胞做任何處理，且可同時通入多條樣品流進行計數，可提高細胞偵測效率。

　　本研究利用微細加工技術，製造微型多管道流式細胞儀晶片。以生物相容性佳且價格便宜之鈉玻璃為基材，批次製作微管道及微電極晶片。晶片製作完成，以不同尺寸之聚苯乙烯珠及人類紅血球細胞測試晶片，實驗測試得樣品流中之大小聚苯乙烯珠流出管道的粒子數濃度誤差在3％以內，計算之粒子數目誤差在1％以內，紅血球細胞的誤差則為7％，實驗結果顯示細胞計數誤差極小，證明本研究之新型多管道流式細胞儀是一種很好的細胞計數方法。

　　This paper reports a new micromachine-based flow cytometer capable of parallel processing of cell/particle counting and sorting using microfluidic technology. Hydrodynamic focusing of multiple sample streams is achieved simultaneously by using a new layout of sheath flow channels coming form one single inlet port. Thus only one syringe pump is required during the operation. The flow rate of each sheath flow could be much more stable and uniform with this approach. The images of the focused multiple samples are recorded downstream utilizing a high-speed digital CCD camera. Digital image processing technique is then used to count the number of the cells/particles and measure the speed of the cells/particles at the same time. Moreover, the size of the cell/particle can be identified using the image detection system. Theoretical models based on a “flow-rate-ratio” method are used to predict the width and the position of the multiple focused streams, which could be incorporated with digital image system. Experimental data are found to be highly consistent with theoretical results. Subsequently, cell/particle sorting could be achieved using dielectrophoretic (DEP) forces generated by built-in micro-electrodes downstream. The proposed multi-cell-line flow cytometer is fabricated in low-cost soda-lime glass using a rapid fabrication process. Experimental data show that the developed device can successfully detect the number of the cells/particles in two parallel sample streams and the velocities of the cells/particles in each cell line as well. Low counting error and high counting reliability are also verified by counting a mixture of polystyrene beads with different sizes. Human red blood cells are also used for cell counting test. Moreover, cell/particle counting has been demonstrated successfully. The throughput and the performance of the cell counting/sorting device could be greatly improved due to the development of the proposed methods.

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