Smart and user-friendly food quality monitoring using a red-emitting fluorescent probe for volatile primary amine...

Biogenic amines (BAs) are organic nitrogen compounds formed through microbial decarboxylation of amino acids during food spoilage and biological metabolism. Therefore, the development of rapid, selective, and cost-effective detection strategies for BAs is significant for ensuring food safety and quality. In this study, a new dicyanoisophorone-based fluorescent probe (IPC) was developed, capable of fluorescence detection of aliphatic primary amines (e.g., cadaverine and propylamine). The probe exhibited outstanding analytical performance for cadaverine in like propylamine, with a low detection limit (0.61 μM), fast response time (∼2 min), solid-state red emission with a large Stokes shift (∼217 nm), and selective reactivity while remaining unresponsive to other amines. Application-wise, the probe was integrated into test strips and polymer films, demonstrating visible color and fluorescence shifts upon exposure to biogenic amine vapors under daylight and UV illumination. Real-world applicability was validated using shrimp and chicken samples, where BA levels were successfully monitored non-destructively through RGB analysis via a smartphone camera. Furthermore, a sensor array comprising 12 solvent environments revealed distinct digital color and fluorescence fingerprints for three different amines. In summary, the developed IPC-based sensor platform offers a portable, cost-effective, user-friendly, and highly selective approach for the visual and digital detection of biogenic amines.