Biocompatibility of magnetic [Fe.sub.3][O.sub.4] nanoparticles and their cytotoxic effect on MCF-7 cells

• Published in: International journal of nanomedicine 2012-01, Vol.7, p.4973
• Main Authors: Chen, Daozhen, Tang, Qiusha, Li, Xiangdong, Zhou, Xiaojin, Zang, Jia, Xue, Wen-qun, Xiang, Jing-ying, Guo, Cai-qin
• Format: Article
• Language: English
• Subjects: Cancer cells; Drug delivery systems; Drugs; Nanoparticles; Physiological aspects; Properties; Vehicles
• ISSN: 1178-2013
• DOI: 10.2147/IJN.S35140

Background: The objective of this study was to evaluate the synthesis and biocompatibility of [Fe.sub.3][O.sub.4] nanoparticles and investigate their therapeutic effects when combined with magnetic fluid hyperthermia on cultured MCF-7 cancer cells. Methods: Magnetic [Fe.sub.3][O.sub.4] nanoparticles were prepared using a coprecipitation method. The appearance, structure, phase composition, functional groups, surface charge, magnetic susceptibility, and release in vitro were characterized by transmission electron microscopy, x-ray diffraction, scanning electron microscopy-energy dispersive x-ray spectroscopy, and a vibrating sample magnetometer. Blood toxicity, in vitro toxicity, and genotoxicity were investigated. Therapeutic effects were evaluated by MTT [3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2Htetrazolium bromide] and flow cytometry assays. Results: Transmission electron microscopy revealed that the shapes of the [Fe.sub.3][O.sub.4] nanoparticles were approximately spherical, with diameters of about 26.1 ± 5.2 nm. Only the spinel phase was indicated in a comparison of the x-ray diffraction data with Joint Corporation of Powder Diffraction Standards (JCPDS) X-ray powder diffraction files. The O-to-Fe ratio of the [Fe.sub.3][O.sub.4] was determined by scanning electron microscopy-energy dispersive x-ray spectroscopy elemental analysis, and approximated pure [Fe.sub.3][O.sub.4]. The vibrating sample magnetometer hysteresis loop suggested that the [Fe.sub.3][O.sub.4] nanoparticles were superparamagnetic at room temperature. MTT experiments showed that the toxicity of the material in mouse fibroblast (L-929) cell lines was between Grade 0 to Grade 1, and that the material lacked hemolysis activity. The acute toxicity ([LD.sub.50]) was 8.39 g/kg. Micronucleus testing showed no genotoxic effects. Pathomorphology and blood biochemistry testing demonstrated that the [Fe.sub.3][O.sub.4] nanoparticles had no effect on the main organs and blood biochemistry in a rabbit model. MTT and flow cytometry assays revealed that [Fe.sub.3][O.sub.4] nano magnetofluid thermotherapy inhibited MCF-7 cell proliferation, and its inhibitory effect was dose-dependent according to the [Fe.sub.3][O.sub.4] nano magnetofluid concentration. Conclusion: The [Fe.sub.3][O.sub.4] nanoparticles prepared in this study have good biocompatibility and are suitable for further application in tumor hyperthermia. Keywords: characterization, biocompatibility, [Fe.sub.3][O.sub.4], magnetic nanopa