Core-shell Fe3O4-TiO2 nanoparticles via surface treatment for plasmid DNA purification

Magnetite (Fe3O4) and titanium dioxide (TiO2) composites or core-shell structures have been used in various applications owing to the advantages afforded by their combined characteristics. In this study, TiO2 coatings were obtained by an aqueous process under reflux conditions using titanium(IV) isopropoxide as a TiO2 precursor. Before surface coating with TiO2, the Fe3O4 surface was treated using reagents having hy- droxyl, carboxyl group, and citrate bond to enhance the efficiency of TiO2 particle adsorption. The functional groups on the surface of Fe3O4 were expected to act as adsorption sites owing to electrostatic interaction with TiO2 particles. After the TiO2 coating process, the most efficient functional group for coating was identified by various analyses that confirmed the adsorption of TiO2 particles. The surface functional groups and TiO2 particles on Fe3O4 were observed by Fourier transform infrared spectroscopy. The crystal structure after coating was analyzed by X-ray diffraction analysis. Adsorbed TiO2 particles were observed by electron microscopy and elemental composition analysis. Additionally, the suitability of the Fe3O4-TiO2 particles for DNA purification was confirmed by agarose gel electrophoresis tests.(c) 2022 Elsevier B.V. All rights reserved.