ИСТИНА

The iron nanosized particles showing magnetic properties are known to be widely applied in medicine, electronics and environmental protection. In turn, polysaccharide 6-O-Carboxymethylchitin (CMC), derived from biopolymer chitin (poly β-1,4-linked 2-deoxy-2-acetamido-D-glucopyranose), is known to possess biocompatibility, low toxicity, biodegradability, that causes it′s wide application in biochemistry and medicine. Due to such properties we find polymers of chitin-chitosan row promising for creation of composites with metal nanoparticles on their basis. The purpose of the present study was to develop the new composite film materials based on water-soluble chitin derivative – CMC (MW 2.2x105 and carboxymethylation degree 1.0) and iron nanoparticles (Fe-NP). In this investigation we used Fe-NP, which was received by a radiation-chemical way in the reversed micelles of anionic surface-active agent - sodium bis(2-ethylhexyl) sulfosuccinate (АОТ) in isooctane. In our earlier studies for introduction of metal nanoparticles into water polymer solution we used water dispersion of metal nanoparticles (obtained from their miccelar solution). It should be noted, however, that formation of Fe-NP water dispersion is connected with oxidation and destabilization of particles. To overcome such loss of nanoparticles we tried to transfer Fe-NP from their miccelar solution to water polymer solution directly, using ultrasonic treatment of heterophase system. It was shown that intensity of Fe-NP absorption in a polymer solution remained invariable during two weeks (UV-Vis control). With using FTIR it has been found, that metal nanoparticles stabilization in a polymer matrix was caused by hydrogen bounds formation between functional groups of polymer (amide groups) and АОТ (ester groups), and shift of it′s strips of absorption towards long waves. The polymer composite films were prepared from CMC modified with Fe-NP. Note that absorption strips (λmax 290 nm) in Fe-NP – CMC composite films were identical for that of Fe-NP in their miccelar solution in isooctane. Nanoparticles size (2-3 nm) was characterized by TEM. Besides, formation of zero-valent iron nanoparticles was revealed using XRD analysis. The anionic polyelectrolyte CMC can be used successfully as an initial polymeric matrix for creation of Fe-NP – CMC composites. The polymer matrix in such composites is bearing the function of Fe-NP stabilizer. We are grateful to B.T. Dubinchuk for TEM and XRD analysis investigations.