Facile Fabrication of PVA Nanofibers Decorated With Ratiometric Fluorescent Carbon Dots for Chlorpyrifos Recognition With Deep Learning

A portable and intelligent sensing platform was developed for the rapid detection of chlorpyrifos (CPS). A ratiometric fluorescent nanosensor, comprising biomass-derived iron-doped carbon dots (Fe-CDs) as the probe and silver nanoclusters as the internal reference, was immobilized onto a polyvinyl alcohol (PVA) nanofiber membrane via electrospinning. The resulting sensor achieved a limit of detection (LOD) of 13.88 µmol/L for CPS and demonstrated excellent recoveries (98.52%–105.79%) in spiked cabbage samples. A deep learning model, integrated into a smartphone application, accurately quantified CPS by analyzing images of the sensor's visual response, showing a high correlation with actual concentrations ( R 2 = 0.991). This integrated system provides a simple, low-cost, and reliable tool for real-time food safety monitoring, successfully translating visual color changes into precise quantitative data.