Preparation of magnetically recoverable mesoporous silica nanocomposites for effective adsorption of urea in simulated serum

In this study, SBA-15/Fe3O4 nanocomposites were prepared by conjugating Fe3O4 nanoparticles to mesoporous silica SBA-15 particles as magnetically recoverable adsorbents. The physicochemical and magnetic properties of bare and as-prepared samples were characterized using the X-ray diffractometer, transmission electron microscope, Fourier transform infrared spectroscope, porosimeter, and vibrating sample magnetometer. The performance of SBA-15, Fe3O4, and SBA-15/Fe3O4 nanocomposites for adsorption removal of uremic toxin urea in simulated serum was compared at 25 and 37 degrees C. Except for Fe3O4, both SBA-15 and SBA-15/Fe3O4 showed a high and equivalent adsorption ability for urea. Although the surface area of SBA-15/Fe3O4 nanocomposites decreased from 1167 m(2)/g (bare SBA-15) to 311 m(2)/g, the pore volume of SBA-15/Fe3O4 was not greatly decreased because most of Fe3O4 nanoparticles were coated onto the surface of SBA-15 particles. The adsorption mechanism of urea on SBA-15/Fe3O4 was proposed. Finally, the cytotoxicity of SBA-15/Fe3O4 nanocomposites before and after urea adsorption for fibroblast L929 cells was studied. (C) 2018 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.