Transient Assembly of Macroscopically Structured Supramolecular Hydrogels Driven by Shaped Chemical Fuels

Macroscopically structured supramolecular hydrogels areappealingplatforms for broad applications, ranging from biomedicine to softelectronics; yet, the developed examples are usually static, incapableof evolving their structures and properties over time. Here, we showhow the transient assembly of macroscopically structured supramolecularhydrogels can be realized by using shaped chemical fuels. The shapedfuels are made by simply loading high-energy chemicals in solid gelswith well-defined shapes. The loaded fuels can diffuse out and generategradients in the vicinity of the solid gels, thereby driving transientassembly of supramolecular hydrogels that inherit the shapes of thesolid gels. The macroscopic structures and lifetimes of the hydrogelscan be tuned by changing the shapes and contents of the fuels, respectively.Such a shaped fueling dynamic self-assembly strategy is further designedfor dynamic information encryption, whereby the encoded informationcan only be read for one time and within a defined period.