A magnetic phosphorescence molecularly imprinted polymers probe based on manganese-doped ZnS quantum dots for rapid detection of trace norfloxacin residual in food

[Display omitted] •A MQD-MIPs probe has been firstly fabricated for detecting norfloxacin residual in food.•Mn-Zns QDs endow the probe better anti-interference to analyte with self- fluorescence.•Fe3O4 nanoparticles as core improved the separation speed and stability of the probe.•The possible phosphorescence quenching mechanism of MQD-MIPs to norfloxacin was discussed.•The peobe can rapidly detect trace norfloxacin (LOD = 0.80 μg·L−1) within 40 min. This paper reports the development of a novel probe based on magnetic room-temperature phosphorescence quantum dots with molecularly imprinted polymers (MQD-MIPs) for the rapid detection of trace norfloxacin (NFX) residual in complex food matrix. The highly selective probe was constructed by surface molecular imprinting technology using magnetic materials (Fe3O4 nanoparticles) as core, Mn-doped ZnS quantum dots (Mn-ZnS QDs) as phosphorescent materials, NFX as template, 3-aminopropyltriethoxysilane as functional monomer, and tetraethoxysilane as crosslinking agent. The as-obtained MQD-MIPs were characterized in detail by transmission electron microscopy, scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectrometry, and vibrating sample magnetometer. A magnetic strength of 37.64 emu g−1 was recorded. Also, the probe displayed excellent room temperature phosphorescence properties with excitation/emission peaks at 300/590 nm. Under the optimized conditions, the detection time was less than 40 min, phosphorescence intensity varied linearly with concentration from 1 to 90 μg·L−1, and detection limit reached as low as 0.80 μg·L−1. Furthermore, the MQD-MIPs-based probe successfully detected norfloxacin residues in spiked fish and milk samples with recoveries of 90.92–111.53% and RSD