One-pot synthesis of hydrophilic flower-shaped iron oxide nanoclusters (IONCs) based ferrofluids for magnetic fluid hyperthermia applications

Herein, flower-shaped hydrophilic superparamagnetic iron oxide nanoclusters (IONCs) are synthesized via one pot thermolysis of iron acetylacetonate using triethanolamine (TEA) and diethylene glycol (DEG)/tetraethylene glycol (TTEG) mixtures at 9:1, 8:2 and 7:3 (v/v) ratios. The as-prepared 24-29 nm sized IONCs have displayed (i) saturation magnetization (Ms) values of similar to 68-78 emu/g, (ii) hydrodynamic diameters of similar to 95-192 nm and (iii) zeta potential values of +46 to +65 my. Due to relatively high magnetization and water solubility, IONCs (prepared using 8:2 TEA:DEG, and 8:2 & 7:3 TEA:TrEG ratios) based aqueous ferrofluids i.e. NCAFF-1, NCAFF-2, and NCAFF-3 are investigated by calorimetric magnetic fluid hyperthermia (MFH) at 0.5-8 mg/ml concentrations by exposing them to the alternating magnetic fields (AMFs, H*f similar to 2.4-9.9 GA m(-1) s(-1)). The NCAFF-3 has demonstrated excellent time dependent temperature rise (42 degrees C within 0.7-9.7 min) as compared to the NCAFF-1 and NCAFF-2. Moreover, the NCAFF-3 at 0.5 mg/ml concentration has exhibited enhanced heating efficacies with specific absorption rate (SAR) and intrinsic loss power (ILP) values of 142.4-909.4 W/g(Fe) and 4.2-14.7 nHm(2)/kg, respectively. Furthermore, the NCAFF-3 has presented better cytocompatibility, and substantially reduced proliferation capacity of HepG2 cancer cells in in vitro MFH studies. Thus, the IONCs based ferrofluids (NCAFF-3) are very promising candidates for MFH therapeutics applications. (C) 2018 Elsevier B.V. All rights reserved.