A Microfabricated Electrochemical Oxygen Generator for High-Density Cell Culture Arrays

We present a microfabricated electrolytic oxygen generator for use in high-density miniature cell culture arrays.The generator consists of Ti/Pt electrodes patterned at the narrow end of conical hydrophilic silicone microchannels filled with electrolyte.Surface tension forces arising from the conical microchannel geometry push generated gas away from the electrodes and down the microchannel.This bubble motion draws fresh electrolyte from an adjacent reservoir onto the electrodes.The oxygen dosage can be precisely controlled in each generator by pulse width modulation of the electrode potential.We demonstrate devices capable of continuously providing for a wide range of oxygen demands (0-200mmol/g DCW/hr) and operating for days.We also present data on corrosion conditions.We investigate pre-cure silicone additives as an alternative to plasma surface modification to obtain hydrophilic silicone surfaces.Additionally, we assay for the presence of reactive oxygen species (ROS) in aqueous medium bubbled with generated gas.