Sviluppo ed applicazioni biomediche di sistemi nanostrutturati superparamagnetici costituiti da maghemite (SAMN, Surface Active Maghemite Nanoparticles) e bioelementi

With the rapid development of nanotechnology, magnetic nanoparticles are currently being widely studied. It has long been known that the physico-chemical properties of magnetic nanoparticles can be vastly different from those of the corresponding bulk material. In particular, nanoparticles characteristics are: large surface-to-volume ratio, high surface reaction activity, high catalytic efficiency, and strong adsorption ability, which are helpful for the immobilization of desired biosensing molecules. The nanoparticles used in the present research project (called surface active maghemite nanoparticles, SAMN), were synthesized by a new simple method and original procedure in the dimension range around 10 nm, and are characterized by specific chemical behavior without any superficial modification or coating derivatization. These magnetic nanoparticles show high average magnetic moment and superparamagnetic properties, which means that, the particles are attracted by an external magnetic field, but retain no residual magnetism at field removal. Therefore, suspended superparamagnetic particles can be removed from the suspension using an external magnet, but they do not form aggregates after removal of the external magnetic field. An international patent, supported by the University of Padova, was applied about the synthetic method and further applications. Material characterization was carried out by transmission electron microscopy, spectrophotometric and spectrofluorimetric assays, Mossbauer and FTIR spectroscopy, SQUID magnetic measurements in the temperature range 2-300 K and X-ray powder diffraction studies (Acta Biomaterialia, 2012), in collaboration with the Department of Chemical Sciences and the Department of Geo Sciences of the University of Padova and the Centre for Nanomaterial Research at the Palacky University in Olomouc (Czech Republic). The surface of these maghemite nanoparticles was functionalized with proteins of high biotechnological interest, such as horseradish peroxidase, avidin and biotin to ...