Bubbles No More: Trapping and Removal of Gas Bubbles in Single-layer Elastomeric Devices

Unwanted gas bubbles are a practical problem limiting the reliable use of microfluidic systems, particularly for the culture of biological samples. We present a robust, scalable, single-layer strategy for the elimination of gas bubbles from microchannel networks that are defined in gas-permeable substrate materials. Removal rates for nitrogen bubbles were measured in water and ethanol, and compared with numerical predictions. Gas bubbles were removed at rates exceeding 0.14 μL/min in a single trap with a maximal volume of 0.43 μL. Scalability of the design was demonstrated in a parallel configuration of eight traps. The gas removal strategy was applied to the perfusion culture of small blood vessels.