PROPERTIES OF MAGNETOFERRITIN - A NOVEL BIOMAGNETIC NANOPARTICLE

A soluble and biocompatible magnetic material would have many possible applications. An approach to producing biomagnetic nanophase particle s with large magnetic moments is to reconstitute the iron-storage prot ein ferritin under conditions tailored to the synthesis of magnetite, rather than the normal ferrihydrite, in the core. The material produce d in this way is called magnetoferritin. Mossbauer spectroscopy is an ideal technique for characterising such iron-containing nanophase syst ems. The Mossbauer spectra obtained at low temperatures and in large a pplied magnetic fields clearly show that the magnetoferritin core is q uite different to that of ferritin. The changes in the spectra with in creasing applied field indicate that the core is a ferrimagnet. Comput er analysis of these spectra leads to the conclusion that the magnetof erritin core is very similar to the mineral maghemite (gamma-Fe2O3). ( C) 1997 Acta Metallurgica Inc.