Access to potable water is a critical issue globally, and this has required the application of diverse wastewater treatment techniques. This study is centred on the synthesis of magnetite (Fe3O4) based nanomaterial through coprecipitation and modified Stöber method by encapsulating magnetite within a mesoporous silica as a core–shell. Subsequently, the synthesised silica-coated magnetite Fe3O4-SiO2 was further modified by polymerizing its surface with dopamine (DA) in a basic solution, creating Fe3O4-SiO2-PDA. The successful synthesis of Fe3O4-SiO2-PDAnanomaterial was confirmed through various characterization techniques, including scanning electron microscopy (SEM), Energy dispersive x-ray spectroscopy (EDX), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. A batch adsorption experiment was conducted to evaluate the adsorption capacities of the synthesized materials for tetracycline removal from prepared wastewater at 25 °C. After 120 min, the adsorption capacity was determined to be 32.992, 38.928, and 47.55 mg/g for Fe3O4, Fe3O4-SiO2, and Fe3O4-SiO2-PDA, respectively. The results showed that pH significantly influenced the adsorption process and pH 8 was determined to be the optimum pH for the adsorption of tetracycline. The kinetic modelling revealed that the adsorption of TC was best described by the pseudo second order model, while the equilibrium studies indicated that the adsorption followed Langmuir isotherm for both adsorbents and was thus monolayer in nature. Overall finding of the study indicates that the synthesized Fe3O4-SiO2-PDA core–shell exhibits the highest efficiency in the removal of tetracycline from aqueous solution.