Smartphone-Integrated Fluorescent Sensing Array Assembled from Lanthanide Metal–Organic Frameworks for Rapid Identification and Differentiation of Antibiotics in Daily Foods

The excessive use of antibiotics in human healthcare and animal farming presents significant risks to ecosystems and human well-being, prompting the development of diverse detection technologies. Fluorescence sensing arrays have garnered considerable attention due to their cost-effectiveness and ability to detect multiple targets. This work presents a lanthanide metal-organic framework ([Tb₂(H₄(m-dobdc))₂(H₂O)₂(DMF)₂]_n), named CUST-900. We utilized linear discriminant analysis (LDA) and hierarchical cluster analysis (HCA) to analyze the fluorescence sensing array based on Tb-MOF (CUST-900) for five antibiotics. For the first time, CUST-900 was able to effectively distinguish between five antibiotics at different concentrations of one-, two-, and three-component mixtures, demonstrating high sensitivity and 100% recognition accuracy. In particular, the CUST-900 sensor, in conjunction with a smartphone, was used for the visual detection of tetracycline (TC), with detection limits as low as 130 nM. The developed probe has been successfully applied to determine TC in water and honey, achieving recoveries ranging from 96.67% to 101.15% with a relative standard deviation (RSD) of 4.99%.