Mössbauer spectroscopy study of magnetic iron oxide nanoclusters in a biocomposite based on poly(3-hydroxybutyrate) and chitosan

Abstract

The structural, electronic, and magnetic properties of iron oxide nanoparticles encapsulated in biodegradable therapeutic systems based on polyhydroxybutyrate and chitosan have been studied by Mossbauer spectroscopy and X-ray diffraction. It has been shown that, in polymer matrices containing 4 and 8 wt % iron oxide, the latter exists in two different forms: as nanosized (d ≈ 7–8 nm) superparamagnetic clusters and “paramagnetic” Fe3+ ions. It has been demonstrated that cluster nonstoichiometric iron oxide has an inverse spinel structure intermediate between the Fe3O4 and γ-Fe2O3 polymorphs.