Microfluidic High-Power Electroosmotic Pumps Based on Glass Fiber Filters

A surface phenomenon known as the electric double layer effect occurs in a few atomic layers at the fluid–solid interface. By applying an external electric field, this phenomenon is used to generate a fluidic flow, which is called electroosmosis, and the corresponding device electroosmotic pumps (EOPs). In order to immensely increase the fluid–solid contact surface and, consequently, the fluid volume that generates the desired fluidic flow, an EOP employing a glass fiber filter in the main channel is presented in this letter. As a result, our EOP can reach high pressures of up to 400 kPa as well as high flow rates up to the milliliter per minute range. The devised technology enables low-cost EOP fabrication by using a polymethyl methacrylate substrate and mostly thermal-based fabrication processes. In order to address the challenges associated with spurious gas generation due to electrolysis, this EOP uses ion conductive membranes to keep the unwanted electrolysis process outside of the channel. To endure highly aggressive chemical reactions, platinum wires are furthermore employed as electrodes in the EOPs.