Preparation and characterization of magnetic nanoparticles with bifunctional surface layer ≡Si(CH2)3NH2/≡SiCH3 (or ≡SiC3H7−n)

The bifunctional layers of ≡Si(CH2)3NH2/≡SiCH3 and ≡Si(CH2)3NH2/≡SiC3H7−n on the surface of Fe3O4 magnetic particles are obtained by the developed method based on the reaction of hydrolytic polycondensation of tetraethoxysilane and appropriate trifunctional silanes. The DRIFT spectra indicate the formation of the silica bounds framework in the surface layers of magnetite nanoparticles and the presence of related functional groups. The content of amine groups at the level of 1.6–2.2 mmol/g is confirmed by the acid–base titration. The presence of the amine groups along with the methyl (or n-propyl) groups in the surface layer enhances the sorption capacity of samples towards the HSA. The resulting powder materials retain their magnetic properties and are perspective for the usage in medical practice.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Amine and alkyl layers were created on the surface of Fe3O4 by sol–gel technique. ► Bifunctional sorbents with amine and alkyl groups show enhanced sorption capacity towards HAS. ► Obtained powder materials retain their magnetic properties. ► Obtained powder materials can be advanced for use in medical practice.