Surface-coating of Mg0.5Co0.5Fe2O4 nanoferrites and their in vitro cytotoxicity

Abstract

Magnetic nanoparticles (MNPs) are attractive for biomedical applications, as contrast agents for magnetic resonance imaging, hyperthermia treatments, cell labelling, magneto-targeted therapy and drug delivery. Spinel ferrites represent a class of MNPs with unique optical, electrical and magnetic properties. In this study, we synthesized, characterized and evaluated the cytotoxicity of polymer-coated Mg0.5Co0.5Fe2O4 MNPs in human embryonic kidney (HEK293) and cervical carcinoma (HeLa) cells, to determine their future potential in drug/gene delivery. Mg0.5Co0.5Fe2O4 ferrites were synthesized via a glycol-thermal method, and functionalized with chitosan (CS), polyethylene glycol (PEG) and polyvinyl alcohol (PVA). The morphology and structure of all MNPs were characterized using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) spectroscopy. Magnetic measurements at 14 kOe, confirmed the superparamagnetic nature of all MNPs, while XRD patterns confirmed typical single-phase cubic spinel structures with average crystallite size < 12 nm, which decreased upon coating. TEM and NTA displayed small, spherical particles, with some agglomeration, and improved colloidal stability (zeta potential > − 30 mV). In vitro cytotoxicity using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and sulforhodamine B (SRB) assays, confirmed moderate to low cytotoxicity in the HEK293 cells, with lower cell viability observed in the HeLa cells, supporting their use in biomedical applications.