A metal-organic framework-based sensor for specific detection of tetracycline in milk

Molecularly imprinted fluorescent sensors are of interest to researchers due to their specificity, high sensitivity, and stability. In this study, the fluorescence-imprinted sensor (NH2-MIL-53/MIP) for the detection of tetracycline (TC) in animal-derived foods was developed based on the characteristics of luminescent metal-organic frameworks (MOFs) and molecularly imprinted polymers (MIPs). The MOFs provide fluorescence sensing signals and large specific surface areas, while the MIPs provide the specific recognition sites for TC. As a result, the sensor exhibits a wide detection range (0.05-50 mu g/mL), high sensitivity (LOD of 0.006 mu g/mL), fast detection speed and good selectivity. The sensing principle can be attributed to photoinduced electron transfer. Furthermore, the sensor can determine TC in milk with good recovery rates (95.05-104.71 %). This work addresses the limitation of current molecularly imprinted sensors such as slow corresponding speed and limited detection capability, providing valuable insights for target determination in complex systems.