<p>A fluorescent detection platform was designed using boric acid-functionalized terbium metal–organic framework (BA-Tb-MOF) and carboxyl-modified magnetic nanoparticles (MNPs) to identify&#xa0;<i>Salmonella typhimurium&#xa0;</i>(<i>S. typhimurium</i>) bacteria. Firstly, carboxyl-modified Fe₃O₄MNPs were coated with specific aptamer (Apt-MNPs) as the capture probe for <i>S. typhimurium</i>. Then, the Apt-MNPs were added to the bacterial suspension to facilitate the targeted binding. Subsequently, the fluorescent probe (BA-Tb-MOF) was introduced into this solution. The BA-Tb-MOF was strongly attached to the bacterial surface through interactions between BA and glycolipids on the bacterial cell walls, forming a stable complex. As the bacterial concentration increased, the fluorescence intensity of the solution progressively decreased due to the binding and removal of bacteria-Apt-MNPs/BA-Tb-MOF complexes through magnetic separation. Under optimum conditions, the concentration of <i>S. typhimurium</i> and the fluorescence intensity showed an inverse linear relationship within the range of 10¹–10⁹&#xa0;CFU/mL, and the detection limit was 4 CFU/mL.&#xa0;The developed sensor showed high specificity against several other pathogenic bacteria such as <i>E. coli</i>, <i>S. aureus</i>, and <i>P. aeruginosa</i>. The developed fluorescence platform also successfully detected the <i>S. typhimurium</i> in drinking water and egg samples with satisfactory recoveries (83–98%). This strategy can be investigated further for the detection of <i>S. typhimurium</i> and other pathogens in food and clinical samples.</p> Graphical Abstract <p></p>