中文摘要：

研究制作了一种基于水力聚焦效应,可以对多种不同大小细胞进行聚焦排队实验的聚二甲基硅氧烷（PDMS）微流芯片。芯片的制作过程主要包括制作SU—8阳模,然后利用软光刻方法得到PDMS微流沟道,最后与盖片进行键合封装。用COMSOL软件对样本流与鞘流在不同流速比下进行了流体聚焦仿真,得到了样本的聚焦宽度。利用罗丹明B进行了聚焦验证实验,聚焦宽度与仿真基本一致。通过调节流速比,芯片可用于10～60μm细胞的计数与分析,并利用15μm荧光微球进行了微球排队实验,观察到微球以一列的形式排队经过了聚焦沟道。这种微流芯片具有制作方法简便（SU—8阳模可重复使用）、成本低廉、调控方式简单、通用性强等优点。

英文摘要：

Research and fabricate a PDMS microfluidic chip which can implement the focusing quening experiment on different sizes of cells based on hydrodynamic focusing effect.The fabricating process of the chip is as follows：firstly,fabricate male mold of SU—8;secondly,make the PDMS microfluidic channel using soft photo-lithography;at last,bond and packge with the cover.Fluid focusing simulation is carried out under condition of different flow rate ratio between the sample flow and sheath flow via the COMSOL software and obtain focusing width of sample.Use Rhodamine B to carry out confirmatory experiment of focusing,focusing width is consistent with the simulation.The chip can be used for count and analysis of cells of 10 ~60 μm by adjusting the flow rate ratio.And the experiment of queuing of fluorescent microbeads is carried out,it is observed that microbeads pass through the focusing channel in a line.This fabrication method for microfluidic chip have the advantages of simple process（SU—8 male mold can reuse）,low cost,simple adjusting style and versatility.