Figure 1: Simulation Setup. (a) The channel and chamber geometry (all numbers given in [µm]). The cell chamber of interest, in-between the two channels, has dimensions 100[µm] by 250[µm]. The dead end valves are always closed. (b) In reality the distance from the valves to the chamber would be longer, but the channels are pruned in the simulation setup in order to save simulation time. This has no impact on the solution since the diffusion length is smaller than the length of the pruned channels. (c) The left and right channel are opened alternately for 1[s], respectively. Between the flushings, all valves are closed for 119[s].