A sodium alginate-based aggregation-induced emission fluorescent sensor for detecting nitrite in food

A novel sodium alginate-based aggregation-induced emission (AIE) fluorescent probe was developed for the recognition of nitrite (NO₂^-). In this study, cyano-containing moieties were introduced onto oxidized sodium alginate through a Schiff base reaction, and the optical properties and sensing performance of the resulting material were systematically investigated. Its photophysical properties and sensing performance toward NO₂^- were systematically investigated. The probe exhibited a sensitive fluorescence response to NO₂^- over a wide concentration range (0-200 mg/L), enabling quantitative detection in aqueous media (LOD: 6.49 μg/L). Its practical applicability was further demonstrated by the accurate determination of NO₂^- in real sausage samples. Moreover, the material exhibits excellent biocompatibility and effective cell imaging capability, highlighting its broad application potential in food safety monitoring and biomedical imaging.