Using effective and sustainable technologies for food quality evaluation has become imperative due to the growing concerns regarding food safety and security. Fluorescent-based sensing is a rapid monitoring technique for food spoilage detection; however, the technique employs fossil-based compounds for sensor development. Here, a fluorescent sensor for histamine (biogenic amine) as an indicator for the detection of spoilage in the fish matrix was fabricated using 2,5-furandicarboxylic acid (FDCA) as the organic ligand. FDCA is a biobased molecule and serves as a replacement for petroleum-derived terephthalic acid, which is widely used in the synthesis of fluorescent metal-organic frameworks (MOF). Herein we report a MOF that was synthesized using two organic ligands: FDCA and adenine with Fe as the metal center, denoted as Fe-AD-FDCA. The fluorescent sensor was created by covalently bonding methyl red (MR) with an NH2-rich Fe-AD-FDCA framework by post-synthetic modification. When exposed to histamine, the sensor showed a fluorescent emissive response that increased MR emission and produced a distinctly visible color shift from dull pink to blue. By spreading and solidifying MR@Fe-AD-FDCA in the water-phase sodium salt of carboxy methyl cellulose (CMC-Na), portable sensory hydrogels were produced. This fluorescence sensor's ability could be utilized for real-time monitoring of the freshness of raw fish samples.
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