Feedback-Controlled Topological Reconfiguration of Molecular Assemblies for Programming Supramolecular Structures

In biology, nonequilibrium assembly is characterized by fuel-driven switching between associating and nonassociating states of biomolecules. This dynamic assembly model has been used routinely to describe the nonequilibrium processes in synthetic systems. Here, we present a G-quartet-based nonequilibrium system mediated by fuel-driven co-assembly of guanosine 5’-monophosphate disodium salt hydrate and urease. Addition of lanthanum(III) ions to the system caused macroscopic dynamic switching between precipitates and hydrogels. Interestingly, combined analyses of the nonequilibrium systems demonstrated that molecules could switch between two distinct associating states without undergoing a nonassociating state, suggesting a nonequilibrium assembly mechanism of topological reconfiguration of molecular assemblies. We detailed quantitatively the nonequilibrium assembly mechanism to precisely control the phase behaviors of the active materials and, therefore, were able to apply the materials for transient-gel-templated polymerization and transient circuit connection. This work presents a new nonequilibrium system with unusual phase behavior, and the resultant active hydrogels hold substantial promise in applications including fluid confinements and transient electronics.