surface modification of magnetic mnfe_2o_4@sio_2 core-shell nanoparticles with deposited layer of 3- aminopropyl triethoxysilane

Modification of mnfe_2o_4@sio_2 coreshell nanoparticles with (3aminopropyl) triethoxysilane (aptes) was investigated. the magnetite mnfe_2o_4 nanoparticles with an average size of ~33 nm were synthesized through a simple coprecipitation method followed by coating with silica shell using tetraethoxysilane (teos); that has resulted in a high density of hydroxyl groups loaded on nanoparticles. the prepared mnfe_2o_4@sio_2 nanoparticles were further functionalized with aptes via silanization reaction. for having suitable surface coverage of aptes, controlled hydrodynamic size of nanoparticles with a high density of amine groups on the outer surface, the aptes silanization reaction was investigated under different reaction temperatures and reaction times. based on dynamic light scattering (dls) and zeta potential results, the best conditions for the formation of aptesfunctionalized mnfe_2o_4@sio_2 nanoparticles were defined at a reaction temperature of 70 °c and the reaction time of 90 min. the effectiveness of our surface modification was established by xray photoelectron spectroscopy (xps), transmission electron microscopy (tem), fourier transforms infrared spectroscopy (ftir), and vibrating sample magnetometer (vsm). the prepared magnetite nanostructure can be utilized as precursors for synthesizing multilayered coreshell nanocomposite particles for numerous applications such as medical diagnostics, drug, and enzyme immobilization, as well as molecular and cell separation.