Ralf Lenigk

High-Capacity Redox Polymer Electrodes: Applications in Molecular and Cellular Processing

We present methods to fabricate high-capacity redox electrodes using thick membrane or fiber casting of conjugated polymer solutions. Unlike common solution casting or printing methods used in current organic electronics, the presented techniques enable production of PEDOT:PSS electrodes with high charge capacity and the capability to operate under applied voltages greater than 100 V without electrochemical overoxidation. The electrodes are shown integrated into several electrokinetic components commonly used in automated bioprocess or bioassay workflows, including electrophoretic DNA separation and extraction, cellular electroporation/lysis, and electroosmotic pumping. Unlike current metal electrodes used in these applications, the high-capacity polymer electrodes are shown to function without electrolysis of solvent (i.e., without production of excess H+, OH–, and H2O2 by-products). In addition, each component fabricated using the electrodes is shown to have superior capabilities compared with those fabricated with common metal electrodes. These innovations in electrokinetics include a low-voltage/high-pressure electroosmotic pump, and a “flow battery” (in which electrochemical discharge is used to generate electroosmotic flow in the absence of an applied potential). The novel electrodes (and electrokinetic demonstrations) enable new applications of organic electronics within the biology, health care, and pharmaceutical fields.