在本研究中，利用微機電製程技術製造出一個操作方式簡單的
P x Q管道[1](P:流體樣本入口槽數目，Q:流體樣本出口槽數目)微流體晶片，本研究中使用P=3，Q=2之晶片。並且利用電壓驅動產生電滲流，在晶片的前段達成流體聚焦(flow focusing)的效應。晶片中段主要是利用電壓的配置以及時間的控制，再經由一邏輯算式算出要注入樣本傳輸管道(晶片中段管道)的流體樣本長度，使流體樣本能以不同長度依序流入主要管道。最後，在晶片末段，不同長度的流體樣本可以各別的被傳送入不同的出口管道。即是以排列的形式於樣本傳輸管道傳輸不同長度的流體樣本，接著再將不同長度的流體樣本，各自加以分離，達成序列式注射(sequential injection)的功能。

This study proposes a technique for the sequential injection of electroosmotically-driven sample flows in microfluidic devices. The study commences by analyzing the buffer length required to prevent diffusion between successive sample plugs and then develops an analytical formulation to determine the operating parameters guaranteed to ensure deposition of the complete sample plug in the designated outlet reservoir. It is shown that by an appropriate manipulation of the voltages applied to the various inlet and outlet channels of the microfluidic device, samples of different lengths can be delivered automatically and continuously to the specified outlet reservoirs. It is demonstrated experimentally that the injection performance of the microchip can be enhanced via the application of a voltage to the non-receiving reservoir during the injection process to prevent sample leakage. Finally, the experimental and numerical results indicate that the injection performance can be further improved by optimizing the geometrical arrangement of the outlet channels.

1.C. Pang, Y.C. Tai, J. W. Burdick and R. A. Andersen.2006 Electrolysis-Based Diaphragm Actuators Nanotechnology 17 S64–S68.

2. H. Lee, Y. Liu, D. Hamb and R. M. Westervelt. 2007 Integrated Cell Manipulation System-CMOS/Microfluidic Hybrid. Lab on a Chip. 7, 331–337.

3. S. K. Cho, Y. Zhao and C.J. Kim. 2007 Concentration and Binary Separation of Micro Particles for Droplet-Based Digital Microfluidics. Lab on a Chip. 7, 490–498.

4. T. Ito, A. Inoue, K. Sato, K. Hosokawa and M. Maeda. 2005 Autonomous Polymer Loading and Sample Injection for Microchip Electrophoresis Anal. Chem. 77, 4759-4764.

5. B. Samel, P. Griss and G. Stemme. 2007 A Thermally Responsive PDMS Composite and Its Microfluidic Applications Journal of Microelectromechanicalsystems. VOL. 16, NO. 1, February 50-57.

6. J. L. Tanyanyiwa and C. Hauser. 2002 High Voltage Capacitively
Coupled ContactlessConductivity Detection for Microchip Capillary
Electrophoresis. Anal. Chem. 74 , 6378 -6382.

7.L.Ren, D. Sinton and D. Li. 2003 Numerical Simulation of Microfluidic Injection Processes in Crossing Microchannels.J. Micromech. Microeng. 13, 739–747.

8.L.M. Fu, R.J. Yang, G.B. Lee and H.H. Liu. 2002 Electrokinetic Injection Techniques in MicrofluidicChips. Anal. Chem.74, 5084-5091.

9.L.M. Fu, R.J. Yang and G.B. Lee. 2003 Electrokinetic Focusing Injection Methods on Microfluidic Devices. Anal. Chem.75, 1905-1910

10.I. Glasgow and N. Aubry. 2003 Enhancement of Microfluidic Mixing
using Time Pulsing. Lab on a Chip. 2003, 3, 114–120.

11.H. Chen and J. C. Meinersa. 2004 Topologic Mixing on a Microfluidic Chip. Applied Physics Letters. Volume 84, Number 12,2193-2195.

12.J.T. Coleman, J. McKechnie and D. Sinton. 2006. High-Efficiency
electrokinetic Micromixing through Symmetric Sequential Injection and Expansion. Lab on a Chip. 6, 1033–1039.

13.W.B. Du, Q. Fang and Z.L. Fang. 2006 Microfluidic Sequential
Injection Analysis in a Short Capillary. Anal. Chem. 78, 6404-6410.

14.Y.J. Pan, J.J. Lin, W.J. Luo and R.J. Yang. 2006 Sample Flow
Switching Techniques on Microfluidic Chips. Biosens, Bioelectron.
21, 1644-1648.
15. L.M. Fu, R.J. Yang, G.B. Lee and Y.J. Pan. 2003. Multiple Injection Techniques for Microfluidic Sample Handling. Electrophoresis. 24, 3026-3032.
16. S.M. Shin , I.S. Kang and Y.K. Cho. 2005. Mixing Enhancement by using Electrokinetic Instability under Time-Periodic Electric Field. J. Micromech, Microeng. 15, 455-462.

17. M.H. Oddy, J. G. Santiago, and J. C. Mikkelsen. 2001. Electrokinetic
Instability MicromixingDepartment of Mechanical Engineering. Anal.
Chem. 73, 5822-5832.

18. E. Biddiss, D. Erickson and D.Q. Li. 2004. Heterogeneous Surface
Charge Enhanced Micromixing for Electrokinetic Flows. Anal. Chem.
76, 3208-3213.

19. F. Scho¨nfeld, S. Hardt, M. Bo¨hm, R. J. Pu¨schl, M. Walder and
B.Wenclawiak 2006. Electroosmotic Flow Patterning using Microfluidic Delay Loops. Lab on a Chip. 6, 1525–1529.

20. N.T. Nguyen, and X.Y. Huang. 2005. An Analytical Model for Mixing Based on Time-Interleaved Sequential Segmentation. Microfluid, Nanofluid. 1, 373–375.

21. C.H. Wu and R.J. Yang. 2006. Improvements on the Electrokinetic
Injection Technique for Microfluidic Chips. Electrophoresis.27,
4970-4981.

22. A. N. Chatterjee and N. R. Aluru. 2005.Combined Circuit/Device
Modeling and Simulation of Integrated Microfluidic Systems.
Journal of Microelectromechanicalsystems.Vol.14,No.1,81-95.

23.C H. Lin，G. B. Lee，Y. H. Lin and G. L. Chang，”A Fast Prototyping
Process for Fabrication of Microfluidic Systems on Soda-Lime Glass.”，Journal of Micromechanics and Microengineering，11，726-732，2001.