Ratiometric sensing based on self-assembled dipeptide: Color-resolved visualization of quantified evaluation for...

Biogenic amines (BAs) are important indicators for assessing the freshness of meat products. In this study, we synthesized fluorescent nanoprobes based on self-assembled dipeptides, which not only enable fluorescence sensing of various BAs but also facilitate the rapid and efficient detection of meat spoilage through ratiometric sensing. The ratiometric fluorescent probe, synthesized by combining self-assembled dipeptide with methyl red, exhibited dual-emission peaks at 400 and 610 nm. This design effectively minimized interference from instrumental parameters and environment factors, ensuring accurate, efficient, and sensitive detection of BAs. Within the linear range of 1 to 50 mg L^-1, the detection limits for histamine (His), tyramine (Tyr), putrescine (Put), tryptamine (Try), and spermine (Spm) were 0.38, 0.37, 0.30, 0.40, and 0.51 mg L^-1, respectively, with a detection time of 12 min. In addition, the prepared test strips could effectively monitor meat spoilage at different temperatures, demonstrating good potential for practical applications.