Insights into the synthesis optimization of Fe@SiO2 Core-Shell nanostructure as a highly efficient nano-heater for magnetic hyperthermia treatment

Maintaining the intact iron core, protecting the extra iron ion release, and generating biologically sufficient heat, are the critical aspects for magnetic hyperthermia treatment (MHT). Thus, the composition of silica-coated nanoscale zero-valent iron (nZVI) was optimized by applying response surface methodology (RSM) and changing the molar ratio of tetraethyl orthosilicate (TEOS) and iron(II) sulfate (FeSO4 center dot 7H(2)O) as the silica and iron precursors, respectively. The TEOS/FeSO4 center dot 7H(2)O molar ratio of 1.67 results in the maximized saturation magnetization (99.3 emu/g) and the crystalline phase of pure iron. In comparison with the previously reported studies, the synthesized core-shell nanostructures demonstrate superior heat production features. As silica coating protects the inner core from oxidation and results in more effective heat-generating seeds, nanostructures with a higher amount of silica precursors, i.e., 10.3 mM, demonstrate an efficient specific absorption rate (SAR). Moreover, the medium and higher TEOS amounts represent acceptable cytocompatibility up to 125 mu g/mL and 250 mu g/mL, respectively. In vitro hyperthermia evaluation depicts the cancer cell viability reduction indicating the hyperthermiainduced apoptosis. Based on the data mentioned above, we could introduce a potential successful nanoparticle for magnetic hyperthermia treatment. (C) 2021 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.