Intracellular distribution of Fe$_{3}$O$_{4}$ nanoparticles in both human and mouse cells

In recent years there has been an increasing interest in developing Fe$_{3}$O$_{4}$ nanoparticles for biomedical applications including targeted drug delivery and magnetic resonance imaging. Understanding of the intracellular distribution of these nanoparticles is crucial when considering these nanoparticles for specific applications. We have synthesized Fe$_{3}$O$_{4}$ nanoparticles having average size of 14 nm using a co-precipitation technique, which were coated with dextran. We studied the structural and morphological characteristics of the nanoparticles using x-ray diffraction, electron microscopy, dynamic light scattering, and zeta potential measurements. We also characterized the magnetic properties of the nanoparticles. In order to investigate the intracellular distribution of these Fe$_{3}$O$_{4}$ nanoparticles, we functionalized the dextran coated Fe$_{3}$O$_{4}$ nanoparticles with a fluorescent dye, Fluorescein isothiocyanate (FITC), and cultured them with both mouse insulinoma MIN 6 cells and human pancreatic MIA PaCa 2 cells. Using optical microscope we investigated the intracellular distribution of the nanoparticles and the effects on cell growth.