Host‐Guest Recognition‐Driven Colorimetric/Fluorescent Nanosensor Enables Ultrasensitive Hazardous Dodine Detection With Versatile Applications

ABSTRACT Global pesticide reliance since the 20th century has paradoxically secured food supplies while escalating ecological/health crises, demanding advanced monitoring technologies. The fungicide Dodine (DD) epitomizes this dilemma: exceeding 10 000 metric tons of annual use for crop protection, its environmental persistence from farming mismanagement causes ecosystem‐scale bioaccumulation, yet multifunctional real‐time detection platforms remain critically underdeveloped. Herein, we pioneer cucurbit[7]uril‐engineered nanoarchitectures ( RhB‐Py1&Q[7] ) via employing a host‐guest recognition strategy. This molecular engineering strategy suppresses fluorophore aggregation while boosting photostability, yielding a dual‐mode (colorimetric/fluorescent) rod‐shaped nanosensor with ultrafast response times (∼12 s), ultra‐trace sensitivity (LOD = 6 n m ), and exceptional selectivity. Field trials demonstrated on‐site detection and robust DD quantification across crops, soils, and aquatic systems. Beyond conventional detection applications, the platform transcends first employed as programmable fluorescence encryption. Biological investigations revealed transformative insights: real‐time mapping of fungal membrane disruption elucidates antifungal action; zebrafish models expose hepatic‐intestinal bioaccumulation pathways; plant studies decode apoplastic transport mechanisms. Overall, this work not only expands supramolecular chemistry's applications for developing stable fluorescent sensors but also informs analytical tool development for food safety monitoring, antifungal mechanisms, and information encryption.