Figure 22.

(a) Schematic illustration of oxygen delivery under in vitro (left) and in vivo (right) conditions. (b) Schematic illustration of alternates to improve O2 delivery. Spinning of the roller bottle (top left) on its longitudinal axis allows for oxygen diffusion between the cells and the gas that passively diffuses into the bottle through the permeable lid. In the bioreactor (bottom left), the well-oxygenated medium is stirred continuously by an agitator to abolish oxygen gradients. Microfluidic slides (top right) allow for the flow of the oxygenated medium equilibrated with precise oxygen concentrations over cells attached to the microscope slide. Oxygen-permeable plastic membranes (bottom right) allow the direct diffusion of oxygen from the bottom of the wells, bypassing the diffusion barrier created by the medium above and allowing for more precise control of oxygen conditions at the cellular level. Reproduced from Trenton L. Place et al. [135].