Facilely Processable Dual-Color Ratiometric Fluorescent Sensors for Highly Sensitive Detection of Food Spoilage

Spoiled food, especially seafood, poses a huge challenge to food safety and human health, which should be addressed through early monitoring and warning of freshness. Despite the fact that several food colorimetric sensors have been reported recently, only a small number of them can match the demands of easy manufacturing, high sensitivity, and satisfactory reliability. Herein, we report a type of dual-color ratiometric composites as fluorescent sensors (DUCS) with good processability, which offers the superior real-time and visual detection of seafood spoilage. A visually detectable colorimetric sensitivity under portable UV light irradiation has been achieved for seafood stored at room temperature for 4–6 h (response time variable with different food ingredients). Moreover, the ease and versatility of our formulation, composed of organic fluorophores, polymers, and additives as composites, has enabled facile processing, including drop-coating and stamp-patterning, which would facilitate a broad scope of applications for food sensing and beyond.