Amines are ubiquitous in biological world, but are toxic and harmful in nature. Detection of biogenic amines that are released from spoiled seafood, meat, or dairy products is an important task to maintain the quality and safety of these packaged foods. To this endeavor, herein we report pyrylium salts that are capable of sensing various amines by rapid change of fluorescence color or intensity. In molecular level, this change of fluorescence is rooted to the formation of pyridine or analogous product that have distinct optical property. The pyrylium salts are capable of efficiently sensing amine vapors or amine solutions both in solid state and in solution state and thus demonstrating a multiphase sensing platform. Utilizing the excellent sensing property, we have employed our pyrylium compounds as spoilage indicator for food products such as fish, meat or cheese which relies on sensing biogenic amines released from these spoiled foods and provide optical response. Prominent change in visible and luminescence color was observed within 4− 18 h of packaging at room temperature (∼33 °C). Considering the rapid response for biogenic amines, these molecular sensors have great potential to be utilized for food packaging industry, medical diagnostics, or other sensory devices.

Heterocyclic compounds are an inevitable part of our life. These important classes of molecules have a wide range of applications starting from life-sustaining drugs to agrochemicals. Numerous methods, including metal...