Nov 5 th – 7 th , Brno, Czech Republic, EU SYNTHESIS AND CHARACTERIZATION OF PEG-SILANE FUNCTIONALIZED IRON OXIDE (II, III) NANOPARTICLE AS POTENTIALMRI CONTRAST AGENT Polina RUDAKOVSKAYA, Olga METELKINA, Elena BELOGLAZKINA, Nykolay ZYK, Alexander SAVCHENKO, Igor SCHETININ, Sergey SALIHOV, Maxim ABAKUMOV, Nataliya KLYACHKO, Yuriy GOLOVIN, Alexander MAJOUGA National University of Science and Technology “Misis”, Lomonosov Moscow State University, Chemistry department,Russian National Research Medical University,DerzhavinTambov State University polina-rudakovskaya@org.chem.msu.ru Abstract Herein we report the synthesis, functionalization and characterization of superparamagnetic and ferrimagnetic iron oxide (II, III) nanoparticles with different shape and size. Using a number of chemical methods magnetite nanoparticles having a spherical shape and size: 9 nm (coprecipitation), 22 nm and 50 nm (redox reaction), and 40 nm cubes were synthesized. Special attention in this paper is devoted to covalent modification of magnetite nanoparticles by polymers, such as silane-polyethylene glycol (Peg- silane). The major advantage of modified by polymer magnetic nanoparticles is low toxicity, colloidal stability of prepared magnetite nanoparticles and possibility for post functionalization. We determined coercivity and saturated magnetism. Also, the relaxivity T2 was measured by magnetic resonance imaging (MRI). Prepared nanoparticles have great interest and potential for use in biomedical imaging. Keywords: Magnetic nanoparticles, polymer coating, MRI agents, functionalization of nanoparticles 1. INTRODUCTION Nanomaterials have attracted interest during the last decade as they exhibit unique properties compared with corresponding bulk materials [1-3]. Nanomaterials based on metal oxides are widely used in different fields of science and technology [4].Magnetic iron oxide nanoparticles with functionalized surface have shown great potential applications in biomedicine and pharmacology, including magnetic resonance imaging (MRI) contrast enhancement [5], targeted drug delivery [6], hyperthermia [7], etc. All these applications require that these nanoparticles have been biocompatible and nontoxic. Also, magnetic nanometer-scaled materials, generally smaller than 100 nm, exhibit very different magnetic properties [8-10]. Nowadays, many studies highlight the multimodal imaging and the last advances in theranostic which combines diagnosis and therapy. Magnetite nanoparticles synthesis can be carried out by several syntheticapproaches in organic [11] or water solutions [12], but all of them have advantages and disadvantages. In this work we used various procedures for optimal synthesis of magnetic nanoparticles with different size and narrow size distribution. The main problem with water solution of magnetite nanoparticles istheir colloidal stability. To solve this problem we made the covalent surface modification of obtained particles through the coating with3- aminopropyltriethoxysilane (APTES) coupled with a polyethylene glycol (PEG). 2. EXPERIMENTAL SECTION 2.1. Mesurements TEM: Transmission electron microscope JEOL JEM-2100F/Cs/GIF (200 kV, 0.8 A) DLS: ZetasizerNano ZS (173°) with He-Ne laser (633 nm, 5 mV)