A novel flavonol-based self-assembled sensor with high sensitivity to biogenic amines and application in detection of fish and prawn freshness

Biogenic amines (BAs), such as cadaverine (Cad), putrescine (Put), and spermine (Spe), serve as critical indicators of meat freshness. In this study, we developed a novel flavonol-derived fluorescent probe, 4-(3-((4-cyanobenzoyl)oxy)-4-oxo-2-(2,4,6-trimethoxyphenyl)-4H-chromen-7-yl)benzoic acid ( CTBA ). CTBA exhibited a sensitive and selective fluorescence response to BAs, with a pronounced emission peak at 510 nm that intensified proportionally with BA concentration. For Cad, the probe demonstrated a linear detection range of 0–45 μM, achieving a low limit of detection (LOD) of 0.36 μM. The interaction mechanism between CTBA and cadaverine was validated through 1 H NMR and high-resolution mass spectrometry (HRMS). Furthermore, a composite fluorescent film was fabricated by spin-coating CTBA with ethyl cellulose (EC), leveraging hydrogen-bonding interactions. This film was successfully applied for real-time monitoring of freshness in fish, and prawn. Our work introduces a pioneering bifunctional material capable of dual-purpose packaging and freshness detection, offering significant potential for enhancing food safety protocols.