Intelligent biogenic amine-responsive fluorescent label for visual and real-time monitoring of seafood freshness

A zein-based film functionalized with fluorescent dyes was constructed for visual, real-time monitoring of seafood freshness. The addition of fluorescent dyes had no significant effect on the mechanical property or water sensitivity of the zein-based film, and the fluorescent film exhibited dual emission response. When exposed to ammonia, fluorescein fluorescence increased whilst the fluorescence of rhodamine B was undisturbed. The fluorescent film presented a clearly distinguishable color transition from pink to green. Sample detection tests showed the fluorescent film served successfully as a response label for on-site visual detection of seafood freshness. Development of this intelligent fluorescent film provides a new platform for food safety and quality monitoring, benefiting economic value and public health.