Programmable Fabrics of Enzyme-Responsive Amphiphiles: A Multiscale Platform for Hierarchical Mesophase Transformations.

Systems capable of undergoing a controlled cascade of mesophase transitions across hierarchical scales represent a novel class of dynamic materials. Here, we describe an electrospun polymeric fabric composed of enzyme-responsive di- and triblock copolymers that undergoes a hierarchical cascade of four distinct mesophases. Initially, on immersion in water, the macroscale fabric dissolves, forming nanoscale micelles. Enzymatic degradation of the diblock components triggers a transition into a triblock-based hydrogel. Finally, the enzymatic degradation of the hydrogel into hydrophilic polymers leads to complete dissolution. By adjusting the di- and triblock ratios, we can finely tune the fabric's dissolution rate. Moreover, the fibers can encapsulate hydrophobic agents, which are retained within the micelle and hydrogel phases, enabling their controlled release. This cascade of mesophase transitions, from a macroscopic solid to nanoscale assemblies, organized hydrogels, and eventual molecular dissolution, demonstrates sophisticated hierarchical control, unlocking new opportunities for biomedical applications of programmable materials.