Ligand-Triggered Topology Switching Converts Transient Recognition into Durable Nanofibrillar Anchoring

Converting transient molecular recognition into persistent interfacial architectures under nonequilibrium conditions remains a fundamental challenge in supramolecular chemistry. Here, we report a ligand-triggered topology-switching strategy that overcomes hemodynamic washout by coupling receptor engagement with an in situ phase transition. Rationalized as a kinetically trapped metastable assembly, our system circulates as discrete nanospheres but executes a cooperative topological switch into an entangled nanofibrillar network upon specific integrin recognition. This ligand-induced fibrillation shifts the assembly from a mobile to an adhesive state, transforming short-lived binding events into durable interfacial retention. Using thrombosis as a stringent model, we demonstrate that this mechanism enables site-specific anchoring and gated bioactivity, effectively restoring vascular homeostasis. These findings establish ligand-triggered topology switching as a general chemical paradigm for translating transient biological interactions into robust functional materials.