Augmentation of gas exchange using oscillating microbubble array

We report a novel concept and experimental proof to substantially augment gas exchange between liquid and gas in microfluidics. The key idea is to use an oscillating bubble array to generate microstreaming flows perpendicular to the main laminar liquid stream. As such, the laminar flow stream experiences substantially increased mixing and gas exchange through the adjacent permeable membrane. The patterned PDMS membrane to hold microbubbles was microfabricated and tested for CO
₂
gas exchange. Experimental results show that the proposed concept makes about 2 times augmentation in exchange rate, even in a non-optimized condition. This method may be applied to many gas exchange devices (artificial lung, fuel cell, etc.).