Preparation of Dextran- and Carboxymethyl Dextran-Coated Fe3O4 Nanoparticles for Breast Cancer Cell Labeling and Magnetic Hyperthermia

Breast cancer is one of the deadliest cancers for women, so cell labeling and therapy of breast cancer become imperative. In this work, dextran- and carboxymethyl dextran-coated Fe3O4 nanoparticles (Fe3O4@DEX and Fe3O4@CMD) were well synthesized through the co-precipitation method. The dextran and carboxymethyl dextran coating reduces the average particle size of Fe3O4 nanoparticles from 10.9 to 4.0-5.5 nm, and the coated samples exhibit average hydrodynamic diameters ranging from 31 to 110 nm. The coating promotes the dispersibility of nanoparticles. Saturation magnetization is reduced from 60.3 to 5.6-7.1 emu/g in the coated MNPs due to the large weight ratio of the coating layer and the decrease in particle size. Hemolysis and cytotoxicity assay results indicate the excellent biocompatibility of Fe3O4 nanoparticles. The cellular uptake assay confirms that both dextran- and carboxymethyl dextran-coated Fe3O4 nanoparticles are easily taken in by breast cancer cells. Comprehensively considering dispersion, biocompatibility, and cellular uptake, the Fe3O4@CMD is more suitable for application in the bio-labeling of breast cancer cells. The SAR values of the Fe3O4@DEX and Fe3O4@CMD range from 19.2 to 30.7 W/g. The SAR value is mainly influenced by the hydrodynamic diameter in the coated samples. The Fe3O4@CMD20 shows the maximum SAR value of 30.7 W/g and has potential application in magnetic hyperthermia therapy.