A ratiometric fluorescence sensor based on molecular imprinting technology for rapid and visual detection of norfloxacin

The problem of excessive use and abuse of antibiotics in the environment and food biology is becoming increasingly prominent, and norfloxacin (NOR) is widely used as an inexpensive and broad-spectrum antibiotic drug. Therefore, rapid and effective detection of antibiotics and residues in biological samples has become a demand of the times. This article describes a ratiometric fluorescence sensor based on molecular imprinting technology for the rapid and visual detection of NOR. A linear relationship (R² = 0.9977) was established between the ratio of self-fluorescence of NOR to the reference fluorescence from rhodamine B and NOR concentration (0-400 μg/L), with a detection limit as low as 0.38 ng/mL, the detection time is as short as 8 min, and a high imprinting factor of 4.5. Visual detection of NOR was achieved through the change of fluorescence color from red to blue-purple. Satisfactory detection accuracy (RSD < 3.5 %) and recovery rate (90.03-102.10 %) were obtained through real sample spiking experiments and were highly consistent with HPLC-UV results. This ratiometric fluorescent sensor based on molecularly imprinting technology with high selectivity, sensitivity, rapidity, and visualization for detecting NOR in complex matrices has broad application prospects in the fields of rapid screening and on-site detection.