A Cd (II)‐based Metal–Organic Framework as Switch‐Off Fluorescence Sensors for Antibiotic Detection

ABSTRACT Detecting antibiotic residues is crucial for monitoring their excessive use in healthcare and agricultural practices. Herein, a new 3D metal–organic framework (MOF) containing {[Cd (bpyp)(sdba)]·DMF·2H2O}n (1) (bpyp = 2,5‐bis (pyrid‐4‐yl)pyridine and H2sdba = 4,4′‐sulfonyldibenzoic acid) has been designed and synthesized. MOF 1 displays sensitive detection tetracycline (TCY) with a limit of detection below 7.67 × 10−6 M in an aqueous solution. The detection mechanism involves competitive absorption between MOF 1 and antibiotics, supported by UV–vis spectroscopy and fluorescence lifetime measurements. MOF 1 exhibits a visible fluorescence response to TCY under a 254 nm UV lamp. MOF 1 is applied in the quantitative detection of TCY in lake water with the recovery based on the sensing platform was 92.26–107.54% with RSD (%) less than 4.38%, indicating outstanding reliability.