Barium Hexaferrite Magnetic Fluid: Preparation, Characterization and the In Vitro Identification of Cytotoxicity and Antibacterial Activity

Abstract

As an alternative way to encounter antibiotic-resistant strains of bacteria, we report here a harmless magnetic fluid, which can be targeted to infections using external magnetic field and destroy the target. Ultrafine BaFe12O19 nanoparticles were synthesized using the hydrothermal approach; for the first time, the nanoparticles were coated with citric acid to form a stable aqueous suspension. Characterization of the prepared (coated) oxide was performed on Furrier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDS) analysis and vibrating sample magnetometry (VSM). In vitro cytotoxicity, as well as the antibacterial activity of the surface modified nano-oxide, was measured against eukaryotic cells and samples from both Grams of bacterial strains, respectively. The results showed that the superparamagnetic crystals of barium hexaferrite were successfully surface modified to form a water-based stable magnetic fluid. The magnetic fluid measured to be extremely bio compatible by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) test. Disc diffusion and minimum inhibitory concentration (MIC) methods revealed that the surface modified nano-oxide is fetal for both the Gram-negative Escherichia coli (E. coli) and the Gram-positive Staphylococcus aureus (S. aureus). However, the fatality of the nanoparticles is lower for the Staphylococci strain.