Continuous and Flow-Responsive Oxygen Regulating Platform for Microphysiological Systems

초록

Microphysiological systems (MPS) mimic the in vivo environment and can be used to study physiology and pathology in cells, tissues and organoids. To reproduce the oxygen concentration in vivo, the oxygen concentration should be regulated, and hypoxic conditions are important in many processes. Several methods have been suggested to simulate hypoxic environments inside MPS such as cell chips, but new methods are needed that are non-cytotoxic or minimize the size of incidental equipment. In this study, the new oxygen regulating platform is proposed. To indirectly and totally eliminate oxygen from the medium streaming through the tubing, contact was made between oxygen-permeable tubing and an oxygen scavenging solution. Over a range of flow rates from 10 μL/min to 100 μL/min, a 0% concentration of oxygen was sustained. By mixing deoxygenated medium and non-deoxygenated medium, an oxygen concentration of 3%, corresponding to the hypoxic condition in vivo, was continuously adjusted and maintained for up to approximately 44 hours with no change of the oxygen scavenger. In addition, the specific oxygen concentration can be set in proportion to the flow rate of each medium.