XOXO, Gossip Gel: oscillating chemical reactions facilitate communication between responsive hydrogels*

Responsive hydrogels promise a new world of soft and smart devices that interact with environmental stimuli, such as light-levels, ambient pH, and temperature. In pH-responsive gels, a chemical signal can result in a dramatic shape change which, in turn, squeezes solute out of the gel. This can locally change chemical concentrations, mediating long-distance signalling between isolated hydrogels.

In this talk, I will discuss how coupling an oscillating chemical reaction to a chemo-responsive hydrogel leads to regular repeated shape changes, with the resultant release of solute feeding back into the reaction rate, allowing two spatially-separated hydrogels to “communicate” via synchronisation of their separate chemical reactions. This chemical signalling leading to a physical change allows us to view active gels as proxies for simple life and giving insights into ways in which colonies of microorganisms can signal to each other.