Immobilization of doxorubicin on Fe₃O₄ magnetic nanoparticles modified with iron and silicon glycerolates

Sorption of doxorubicin (Dox) on Fe₃O₄ magnetic nanoparticles coated with iron and silicon glycerolates (ISG-MNPs) was studied. The Dox sorption experiments were carried out in water at different concentrations of ISG-MNPs and Dox. The loading efficiency was assessed by UV spectroscopy. It was demonstrated that at an ISG-MNPs concentration of 0.2 wt.%, an increase in the Dox: ISG-MNPs ratio (from 0.20 to 1.55 w/w) leads to a slow increase in the drug loading capacity (LC) from about 3 to 5%; in this case, the loading efficiency (LE) abruptly decreases from 43 to 6%. A decrease in the ISG-MNPs concentration from 1.0 to 0.5 wt.% (at 0.3 wt.% Dox) leads to an increase in LC from 5.0 to 6.7%. In vitro experiments demonstrated dose-dependent cytotoxicity of the synthesized nanomaterial against human rhabdosarcoma (RD) cells, viz., the statistically significant toxicity of Dox-loaded ISG-MNPs was evident for a nanoconjugate solution with a concentration of 10 µg mL⁻¹, and the cell survival in solutions with a concentration of 100 µg mL⁻¹ was 57%.