Fig. 9: Physical simulation to expose pZCs to physiological conditions relevant to the duodenum.

Addition of water to the edge of the droplet (top, blue dot) allows wetting of glass surface along a line near the circumference of the pZC mixture (depicted as a blue line). Next, a small volume of NaOH solution (red dot) is micropipetted at the edge of the wet line created previously. This system in turn promotes the orderly movement of NaOH into the polymer mixture unidirectionally and gradually.