Targeted Fluoromagnetic Nanoparticles for Imaging of Breast Cancer MCF-7 Cells

To achieve simultaneous imaging and therapy potentials, targeted fluoromagnetic nanoparticles were synthesized and examined in human breast cancer MCF-7 cells. Fe3O4 nanoparticles (NPs) were synthesized through thermal decomposition of Fe(acac)3. Then, magnetic nanoparticles (MNPs) modified by dopamine-poly ethylene glycol (PEG)-NH2; finally, half equivalent fluorescein isothiocyanate (FITC) and half equivalent folic acid were conjugated to one equivalent of it. The presence of Fe3O4-DPA-PEG-FA/FITC in the folate receptor (FR) positive MCF-7 cells was determined via fluorescent microscopy to monitor the cellular interaction of MNPs. FT-IR spectra of final compound confirmed existence of fluorescein on folic acid grafted MNPs. The Fe3O4-DPA-PEG-FA/FITC NPs, which displayed a size rang about 30-35 nm using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), were able to actively recognize the FR-positive MCF-7 cells, but not the FR-negative A549 cells. The uniform nano-sized Fe3O4-DPA-PEG-FA/FITC NPs displayed great potential as theranostics and can be used for targeted imaging of various tumors that overexpress FR.