Effect of the surface treatment on the structural, morphological, magnetic and biological properties of MFe2O4 iron spinels (M = Cu, Ni, Co, Mn and Fe)

Abstract This research proposes to obtain iron spinels MFe 2 O 4 , and their hybrids MFe 2 O 4 @SiO 2 and MFe 2 O 4 @SiO 2 /chitosan (M = Cu, Ni, Co, Mn e Fe) from the surface modification with (3-aminopropyl)trimethoxysilane agent and functionalization with chitosan, and then evaluate them as to their structure, morphology, magnetism and cytotoxicity, towards obtaining biocompatible hybrids for biological applications. The samples were analyzed by XRD, FTIR, SEM, TEM, magnetic measurements and in vitro cytotoxicity. XRD results showed that all samples presented the formation of the desired spinel major phase, with a crystallite size between 12 and 45 nm. According to the morphology and FTIR spectra of the samples, it was possible to confirm the formation of the hybrids. All samples presented soft magnetic material characteristics, exception given to the iron spinels CoFe 2 O 4 , which showed characteristic of hard magnetic material. The best results of cell viability were obtained by the CoFe 2 O 4 , MnFe 2 O 4 e Fe 3 O 4 MNPs and their hybrids.