Smart plant-wearable biosensor for in-situ pesticide analysis

Inspired by the wearable sensors and to meet the demand for rapid and nondestructive detection, we developed a smart plant-wearable biosensor, which can be applied for in-situ analysis of organophosphorus pesticide on crop surfaces. Herein, the serpentine three-electrode system was prepared via the laser-induced graphene (LIG) technology. After transferred by polydimethylsiloxane (PDMS), the stretchable and flexible LIG-based electrode was obtained, which can be well adapt to the irregular surface of crops, such as leaves and fruits. After modified with organophosphorus hydrolase (OPH) and equipped with biocompatible semisolid electrolyte, our plant-wearable biosensor can selectively capture and recognize the methyl parathion and the data can be transmitted to a smartphone device wirelessly, which enable the real-time and in-situ electrochemical analysis of pesticide on the surface of agricultural products. To further enhance the electrochemical performance, gold nanoparticles (AuNPs) were modified on the surface of three-dimensional (3D) porous LIG. Such smart plant-wearable biosensor could be a transformative approach for the in-situ analysis of pesticide residue on crops, which could also promote the development of precision agriculture in the future.