Biofunctionalized ultra-small superparamagnetic nanoparticles for biomedical applications

Over the last decade, nanotechnology has become more relevant in medicine. Among magnetic nanomaterials the future of iron oxide nanoparticles (IONPs) for clinical applications relies on their biocompatibility in moderate doses as well as their ability to be produced in a wide range of sizes and shapes with biofunctionalization potential. Additionally, they show great promise to serve as a cell tracking system in cell-based therapies, and to generate local temperature increases in the magnetic thermotherapy of solid tumours. Thus, the study and development of novel magnetic nanoparticles for biomedical applications is one of the key topics in the field of nanotechnology. Extremely small-sized Fe3O4 superparamagnetic nanoparticles were prepared by coprecipitation, thinly coated with silica and conjugated with FITC, as molecular model specimen. Nanoparticles were characterized by dynamic light scattering (DSL), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD) and surface functional groups and composition were analysed by infrared spectroscopy (FTIR). We assessed the biocompatibility of the magnetic nanoparticles carriers with biofunctional coating (FITC-conjugated) using a colon carcinoma cell line (CaCo-2) as human cellular model. Phase contrast, fluorescence and confocal microscopy analyses were performed to study nanoparticles up-take and internalization