Formation of hydrogel membranes in microchannels and its applications

Formation of membranes in microfluidic channels have been paid attention for their great potentials in separation of components, cell culture supports for tissue engineering and chemical process involving molecular transports. In this study, we introduce a few techniques for formation of hydrogel membranes in microfluidic channels and their applications. First, using enzymatically crosslinkable hydrogels and microfluidic techniques, we realize the width-controllable hydrogel membrane, which was difficult to adjust so far. Second, we suggest a simple one step stamping method for the in-situ formation of hydrogel membranes with various patterns and closed loop shapes. Finally, as the applications of hydrogel membrane, we proposed a multiple directional chemical gradients method, which mimics the real cell environments. Using the proposed membrane formation method, the stable multiple chemical generation was established and the chemotactic response of bacteria was successfully monitored. These results suggest that our suggested systems can be used to understand many cellular activity including cell adhesion and migration directed by chemotaxis or complex diffusions from biological fluids in three dimensional microstructures.