A bi-directional electrochemically driven micro liquid dosing system with integrated sensor/actuator electrodes

In this contribution a micro liquid dosing system is presented, which allows bi-directional manipulation of fluids (i.e. pushing out and pulling in of liquids) by the electrochemical generation and removal of gas bubbles. Bi-directionality is obtained by reversal of the actuation current thereby causing the earlier produced gasses to react back to water. This reduction of gas volume actively pulls liquid back into the system. The electrochemical actuator electrodes have been specially designed to perform the simultaneous measurement of conductivity, via which the total amount of gas can be estimated. As this amount equals the total dosed volume of liquid, dispensed volumes can be determined on-line during experiments.