POSSIBILITY AND MECHANISM STUDY OF LIQUID-METAL BASED MICRO ELECTROOSMOTIC FLOW PUMPS FOR LONG-TIME RUNNING PURPOSE

摘要

This work is a further study of our previous work on liquid-metal based micro electroosmotic flow pump. Injection of room temperature liquid metal (gallium alloy) into microchannels can provide a simple, rapid and low-cost technique for electrode fabrication of electroosmotic flow pumps. In the micro electroosmotic flow pump, the electrode channels are fabricated symmetrically to both sides of the pumping channel in the same horizontal level. In the micropump, PDMS was used to fabricate the microfluidic chip and the liquid metal channel was separated from the pumping channel by a PDMS gap (≤40μm). Although the PDMS is insulative, small current was still found when voltage was applied on the electrodes and the electrical field successfully drove the fluid in the pumping channel. This liquid-metal based micropump can be very easy for fabrication and integration. This study is focused on the possibility and mechanism study of this liquid-metal based EOF pump to see if it can be used for long-time running. The experimental study shows that the pump works very stable and perfect for long-time running applications such as implantable medical devices.