Abstract
In this thesis, the electrolysis-bubble-actuated micropump which takes advantage of EWOD (Electrowetting-on-Dielectric) to approach the feature of 1xN microfluidic switches is reported. With the time-sequence power control, the microfluid can be transported by using the electrolysis-bubble actuation and directionally controlled by tuning the surface property of the microchannels via EWOD. The advantages of this proposed micropump design not only achieve a net pumping flow but also integrate the switch function without the drawbacks that exist in the early reported micropumps and microfluidic switches, such as the complicated moving valves, large/long nozzle-diffuser structure, and high power consumption. Here we describe the design, operation principle and preliminary results of this micropump. Micropumps and microfluidic switches have a variety of applications. Many mechanisms and designs have been reported for the development of micropump and micro flow switches. Among them, electrolytic-bubble actuation is one of those mechanisms to pump micro flow moving forward. However, few microfluid systems take advantage of embedded micropumps for microfluidic switches. In this research, we focus on the development of hybrid functional microfluidic components, the switchable micropumps, which are capable of precisely pumping and dispensing continuous fluid sample into the desired reservoirs. The maximum pumping volume of one cycle is about 15nl. It takes 10 seconds to finish whole process. For the reasonable estimation in our design, the maximum pumping flow rate of this pump is 90nl/min.