A key fundamental difference between CellASIC's microfluidic format and conventional cell culture methods is the use of continuous flow transport. The basic reasoning is that since cells in nature (and in your body) exist in a dynamically flowing environment, it is advantageous to recreate this property in the laboratory.

The mechanics of flows on the microscale are highly laminar. This means that there is no turbulence, and fluids follow well defined streamlines with only diffusive mixing. For a microfluidic cell culture system, it is important create a situation where solutions can be rapidly transported from upstream reservoirs to the cells, yet to have a low shear, "gentle" exposure in the vicinity of cells. To do this, CellASIC pioneered the concept of using a high fluidic resistance microfabricated barrier to separate flow channels from cell culture chambers (see figure). Analysis of the circuit diagram of this configuration shows that pressure driven flow is isolated to the flow channel, while cells will receive nutrients via diffusive transport across the barrier.

It is no coincidence that this design bears striking resemblance to the human micro-vasculature, where you have flow channels (capillaries), resistance barriers (endothelial layers), and cell areas (interstitial spaces), all carefully arranged with micron-scale precision.