Electrowetting-based actuation for microinjection

We propose a micro pipette which has a pumping and ejecting function based on the principle of electrowetting on dielectric (EWOD). The pipette was fabricated through a simple process of depositing and patterning conductive materials and hydrophobic polymer coatings on the inside and outside of a pulled glass tube. We estimated the amount of the controllable water theoretically. The pipette was designed to pump up liquid of 50 nl at a driving voltage of 250 V. Capillary rise and depression were then observed in a fabricated pipette.