Electrochemically Growing Hydrogels to Control Stiffness

At high pH many low molecular weight gelators (LMWG) are dispersed in solution. When a trigger is applied to lower the pH the gelator molecules self-assemble into one dimensional fibres ~10 nm in length. These fibres then entangle to immobilise water to form a gel. We grow gels electrochemically by oxidising hydroquinone on a glassy carbon electrode. The resulting oxidation sets up a pH gradient from low at the electrode surface to high in the bulk solution. The area of low pH triggers the self-assembly of LMWG at the electrode surface. Unique to this method the localised gelation allows for gels to be formed on patterned surfaces to any size or thickness required. Furthermore, we can control the stiffness of the gels by altering the electrochemical properties applied. We require SANS to help us identify fibre length and thickness and how this relates to the applied current.