Disposable luminescent ratiometric sensor based on Tb3+/Eu3+ co-doped silica film for biogenic amines detection in foods

Biogenic amines (BAs) are potentially harmful biomolecules, formed during food degradation by microorganisms, which represent an issue in the food sector. The evaluation of such molecules in foods needs to be assessed by employing simple and low-cost devices to be used in a practical way in quality control operations. This work reports a sensor platform based on a lanthanide-doped silica film that uses 4,4,4-trifluoro-1-phenyl-1,3-butanedione (BTFA), a diketone molecule, as antenna. Using paper as a sensor film substrate, cheap sensors were obtained for the detection and discrimination of numerous amines, with a special emphasis on BAs. By using BTFA as an antenna, significant and fast changes in emission colour were observed after the sensor exposure to amine vapours. The sensor displays characteristic colours for different amines, which results from significant differences in the Eu 3+ /Tb 3+ emission intensity ratios. The obtained combined colours response, allows an accurate amine differentiation, either visual or spectroscopic. The sensor was applied to real samples to identify the degradation process of fresh fish, resulting in notable changes during the studied period. • Disposable paper-supported ratiometric sensor with a Tb 3+ /Eu 3+ co-doped silica film. • The developed luminescent sensor exhibited notable colour changes for amine vapours. • The sensor showed high sensitivity for biogenic diamines. • The paper tags were successfully used for visual monitoring of food spoilage.