Interface-Adaptive Dual-Color Hydrogel with Self-Repairing Function and High Adhesion as Flexible Wearable Sensor for Minimally-Invasive Monitoring Pesticide Residue in Living Crop.

Harnessing dandy mechanical property, hydrogels facilitate the construction of wearable fluorescence sensors for minimally-invasive monitoring pesticide residue in living crops, while the interface self-adaptability and detection accuracy remain hugely challenging. Herein, blue-emission aggregation-induced emission nanoparticles (b-TPE NPs) and red-emission Mn-doped ZnS quantum dots (r-Mn@ZnS QDs) are encapsulated inside agarose, borax, and polyvinyl alcohol-co-constituted hydrogel to construct dual-color TPE@Mn@ZnS@AG@PVA as wearable crop sensor. Owing to specific recognition of r-Mn@ZnS QDs by thiophannate-methyl (TM), the customized TPE@Mn@ZnS@AG@PVA shows a gradual color evolution from reddish purple to blue with high resistance to environmental and experimental interferences via quenching r-Mn@ZnS QDs' fluorescence by target-induced aggregation and photo-induced electron transfer while acting negligible disturbance in blue fluorescence of b-TPE NPs, consequently achieving TM dual-color assay with limit of detection at 0.045 µg mL-1. Additionally, TPE@Mn@ZnS@AG@PVA fascinates smart interface self-adaptability, high adhesion, and outstanding self-repairing function, and then is pasted onto the interfaces of crops to deliver on the sense pesticide residue data in minimally-invasive manner, leading to the monitor of dynamic TM degradation. This study offers an in-depth penetration into dual-color wearable sensor with distinctive features for minimally-invasive monitoring pesticide residue in living crops, advancing the development of wearable crop sensors and precision agriculture.