Microfluidic Oxygen Control: Effect of Microfluidic Device Geometry on Oxygen Gradient Stabilization

Air pollution contributes to more than 62,000 lung cancer deaths worldwide and an additional 712,000 cardiac and respiratory diseases per year. To raise public awareness of the hazards, the Environmental Protection Agency is working to make air sensors, which detect more than 180 hazardous air pollutants, available for the public to observe the air pollutants and safety risks of the air we breathe. Currently, since air sensors cost thousands of dollars, it is only available for the government. However, we can create a cheaper, smaller microfluidic air sensor to raise public awareness of air pollution. To do so, we are identifying which microfluidic device geometries allow the most oxygen molecules to pass quickly through the polydimethylosiloxane (PDMS) membrane by flowing oxygen and nitrogen molecules into different microfluidic devices. The results demonstrate that device 150528A and device D150126A12J, both devices with smaller channel lengths, displayed the quickest diffusion rate of oxygen through the PDMS. This demonstrates that as the channel length decreases, the diffusion rate increases, and thus, devices with shorter channel lengths will provide the most accurate and efficientdetection of the air pollution