Engineering an AIE-Peptide Synergistic Sensing Platform Coupled with Smartphone Analytics for Pesticide Detection in Complex Matrices

This study designed targeted peptide sequences (KKWWWWKEREK, SSKWAWAWKL) based on the electronegativity of organophosphorus pesticides (OPs) and the structural characteristics of the acetylcholinesterase (AChE) catalytic active site. On this basis, the aggregation-induced emission (AIE) molecules Bis-pyrene (BP) and tetraphenylethylene (TPE) were introduced, which interacted electrostatically and covalently with the peptide sequences to induce peptide aggregation, restrict the molecular motion of AIE molecules, and trigger fluorescence enhancement. This sensing system has been successfully applied to the detection of real-world samples including Yellow River water, soil, and eluates from four types of Chinese medicinal herbs, thereby achieving enzyme-free detection of OPs. To enhance the convenience and intelligent capabilities of the detection process, a smartphone application with embedded intelligent algorithms and a portable rapid detection device have been developed. The post-reaction sample simply required placement within the device for imaging, after which the software automatically performed image analysis and concentration calculation. The entire process was completed within several minutes, with user-friendly operation and good potential for practical application. This method offered a novel approach for constructing enzyme-free, visual, and on-site rapid detection systems for OPs.