Enzyme Immobilization by Hydrogen‐Bonded Organic Framework for the Construction of Plant‐Wearable Sensor

Abstract It is of great significance to on‐site detection of pesticides for food safety and pollution monitoring. Plant‐wearable sensors (PWS) are capable of real‐time detection of pesticides on crops, which facilitates the precise application of pesticides and determines whether the plant‐based foods meet the criteria for safe consumption. Herein, PWS are designed by embedding an acetylcholinesterase@poly(allylamine hydrochloride)‐hydrogen‐bonded organic frameworks (AChE@PAH‐HOF) in hydrogel discs to on‐site deliver pesticide‐residue information. The self‐assembly of AChE@PAH‐HOF, achieved via electronic interactions and hydrogen bonding with a crystalline structure‐directing agent, exhibits high catalytic activity and enhances stability. To facilitate long‐term and precision monitoring of organophosphorus pesticides, a PWS is constructed by integrating the AChE@PAH‐HOF into a glycerol‐sodium alginate hydrogel matrix, which provides high water‐retaining capacity essential for sustained operation under high‐temperature. By integrating with the image processing algorithm, the PWS successfully achieves in situ monitoring of pesticide degradation on tomato plants, demonstrating superior accuracy and sensitivity to chlorpyrifos with a detection limit of 1 ng mL −1 . Such a PWS enables non‐invasive, cost‐effective pesticide detection in agricultural settings, supporting targeted crop health management and sustainable precision farming practices.