Molecular Recognition Remolds the Self-Assembly of Hydrogelators and Increases the Elasticity of the Hydrogel by 10⁶-Fold

Addition of vancomycin (1, the receptor) to the supramolecular hydrogel of self-assembled pyrene-d-Ala-d-Ala (2, the ligand) increases the storage modulus of the hydrogel of 2 by about 106-fold. Rheology, microscopy, and spectroscopy investigations suggest that the two-dimensional polymers, formed by the ligand-receptor interaction between 1 and 2, and the self-dimerization of 1, are mainly responsible for the observed dramatic increase in elasticity.