AbstractIn the present work, we synthesized and tested a magnetic molecularly imprinted polymer (magâMIP) sensor for the detection of tetracycline in food samples. Highâperformance liquid chromatography (HPLC) and spectrofluorometry were employed for tetracycline determination. The magâMIP was polymerized on the surface of Fe3O4@SiO2 magnetic nanoparticles using the following substances: 4 mmol of methacrylic acid as the functional monomer, 20 mmol of ethylene glycol dimethacrylate (EGDMA) as the crossâlinking agent, 82.5 mg of benzoyl peroxide as the radical initiator, and 30 ml of acetonitrile as the solvent. The physicochemical characteristics of the proposed magâMIP, including adsorption capabilities and selectivity, were studied and compared with those of a magnetic nonâmolecularly imprinted polymer (magâNIP). The analytical curve was constructed in the range of 1.0Ă10â5â8.0Ă10â5 mol Lâ1, LOD: 3.3Ă10â6, LOQ: 1.1Ă10â5 mol Lâ1. The results obtained from the adsorption analysis showed that the highest adsorption capacity of the magâMIP at equilibrium was 8.247 mg gâ1 and that the tetracycline adsorption process followed the Langmuir adsorption isotherm model and pseudoâsecondâorder reaction kinetics. The proposed magâMIP also exhibited good results when subjected to fluorescence analysis; an increase in tetracycline concentration resulted in an increase in the adsorption capacity, and this led to the effective removal of tetracycline with the reduction of fluorescence intensity. The applicability of the proposed magâMIP was evaluated in honey, cow milk, and egg samples through recovery tests conducted using samples containing spiked tetracycline concentration at two different concentration levels (1.7Ă10â5 and 2.5Ă10â5 mol Lâ1), where we obtained recovery percentages in the range of 73.2â87.2 % (HPLC) and 90.5â103.7 % (spectrofluorometry).