Fabrication of magnetic α-Fe2O3/Fe3O4 heterostructure nanorods via the urea hydrolysis-calcination process and their biocompatibility with LO2 and HepG2 cells

Abstract β -FeOOH nanorods were prepared via the urea hydrolysis process with the average length of 289.1 nm and average diameter of 61.2 nm, while magnetic α -Fe 2 O 3 /Fe 3 O 4 heterostructure nanorods were prepared via the urea calcination process with β -FeOOH nanorods as precursor, and the optimum conditions were the calcination temperature of 400 °C, the calcination time of 2 h, the β -FeOOH/urea mass ratio of 1:6. The average length, diameter, and the saturation magnetization of the heterostructure nanorods prepared under the optimum conditions were 328.8 nm, 63.4 nm and 42 emu·g −1 , respectively. The Prussian blue test demonstrated that the heterostructure nanorods could be taken up by HepG2 cells, and cytotoxicity tests proved that the heterostructure nanorods had no significant effect on the viabilities of LO2 and HepG2 cells within 72 h in the range of 100–1600 μ g·ml −1 . Therefore, magnetic α -Fe 2 O 3 /Fe 3 O 4 heterostructure nanorods had better biocompatibility with LO2 and HepG2 cells.