Smartphone-enabled Fluorescence Sensing Platform for As(V) Detection in Food and Environmental Matrices using CeO2@Curcumin Fluorescent Probe

Fluorescence methods hold great potential for arsenate (As(V)) detection in food safety. However, the development of environmentally friendly and sustainable fluorescence indicators remains at an early stage. Herein, we develop a novel fluorescence sensing platform for As(V) detection. Curcumin (Cur), a plant-derived, non-toxic, and environmentally friendly food additive. Owing to its excellent fluorescent properties, it was used as a green fluorescent indicator in this study. Cerium dioxide nanoparticles (CeO 2 NPs) were synthesized via a green hydrothermal method and then assembled with Cur to form the CeO 2 @Cur fluorescent probe. The detection of As(V) was achieved through an adsorption-desorption mechanism, where As(V) displaces Cur from the CeO 2 surface, thereby restoring its fluorescence. Based on this mechanism, the probe exhibited a linear response (R 2 = 0.991) to As(V) concentrations within the range of 0.10-30.00 μM, with a low detection limit of 25.83 nM. Furthermore, by integrating smartphone-based RGB analysis of fluorescence images, a portable platform was constructed for the on-site detection of As(V). This work thus offers a promising strategy for sustainable and practical solution for As(V) detection in food and environmental samples.