Recognition‐Driven Redox Disassembly of Metal‐Phenolic Nanocapsules for Enzyme‐Responsive Fungicide Delivery

ABSTRACT Stimuli‐responsive nanocapsules (NCs) for precision agriculture often lack the specificity to distinguish subtle biological signals from environmental noise. Herein, programmable NCs are constructed by self‐assembling tannic acid (TA) and Fe(III) into a redox‐active shell around a prothioconazole core. This system operates via a novel recognition‐driven acceleration mechanism rather than traditional enzymatic degradation. Specifically, the binding of Sclerotium rolfsii ‐secreted cellulase to the TA shell acts as a biochemical signal that accelerates the intrinsic reduction of Fe(III) by TA. This recognition event triggers the rapid collapse of the coordination shell, ensuring precise fungicide release at the infection site. A secondary activation pathway involving the pathogen metabolite oxalic acid achieves dual‐stimulus precision control. The molecular mechanism is elucidated through density functional theory (DFT) calculations, and crucially, verified by X‐ray photoelectron spectroscopy (XPS), which provides direct evidence of the enzyme‐facilitated Fe(II) generation. In vitro and in planta assays demonstrate superior disease control, enhanced systemic transport, and significantly reduced phytotoxicity. Furthermore, the NCs exhibit extended soil stability and improved biosafety. This work establishes a materials‐based strategy where biological recognition directly commands phase transitions, offering a new blueprint for on‐demand agrochemical delivery.