Orotic acid as a useful supramolecular synthon for the fabrication of an OPV based hydrogel: stoichiometry dependent injectable behavior.

A facile hydrogelation of a p-pyridylenevinylene derivative (PV) bearing oxyethylene chains in the presence of orotic acid (OA) occurs via various non-covalent interactions. Depending on the PV : OA molar ratio, the hydrogel shows vesicle to either cluster-type aggregate or fiber transformation. Visual color tuning, stimuli-responsiveness and injectable properties of the hydrogel are also observed.