Organs-on-a-chip devices are miniaturized microfluidic devices containing human cells or grown 3D human tissue to recapitulate the in vivo tissue. These devices are claimed to be more accurate models than 2D cell studies, and furthermore they reduce the need for animal experiments.
In organ-on-chip devices, and specifically gut-on-a-chip devices, oxygen concentration is a tremendously important regulatory parameter. In the lumen of the human intestine, the commensal microbiome resides under anaerobic conditions, while a functional intestinal epithelium requires an aerobic environment. This results in a steep oxygen gradient along the radial axis of the intestine. This oxygen gradient is essential to be mimicked in gut-on-a-chip systems to be able to co-culture intestinal epithelial cells with the human microbiome. The oxygen gradient affects the organization, development and dynamic nature of the gut microbiome and the intestinal physiology. A gut-on-a-chip system in which this oxygen gradient can be controlled and monitored would allow to investigate the functioning of the human intestine as well as the effect of disturbances in the human microbiome to the intestinal epithelial cells.