A recyclable and tunable fluorescent sensor for rapid detection of biogenic amines in food

The development of rapid, sensitive, and in-situ methods for detecting biogenic amines is essential for assessing food freshness. In particular, creating recyclable sensing platforms is crucial for enabling continuous monitoring and fostering sustainable analytical practices. However, the limited availability of reversible amine sensors presents a significant challenge in the research field.

Herein, we report the design and synthesis of a push-pull type triphenylamine-dithieno[3,2-b:2',3'-d]pyrrole-based near-infrared fluorescent sensor EBTN1, which demonstrates exceptional selectivity and sensitivity toward primary amines, achieving a detection limit of 160 nM. The sensing mechanism relies on a reversible nucleophilic addition reaction, enabling sensor recycling and minimizing reagent consumption. The methoxyl moiety in EBTN1 serves as a programmable modification site, allowing functionalization without compromising amine-sensing performance, which exemplifies atom-economic design. As a proof-of-concept, a derivative EBTNAld-NHS was synthesized to anchor the sensor onto glass surfaces, fabricating a portable, recyclable sensing device for biogenic amines.

Sensor EBTN1 can be considered as a reusable platform for primary amine detection, offering high selectivity and sensitivity. When fabricated into a sensing glass, it enables real-time monitoring of fish freshness and can be regenerated for at least six cycles, underscoring its viability for sustainable analytical applications in food safety.