Anomalous Mössbauer line broadening for nanosized hydrous ferric oxide cores in ferritin and its pharmaceutical analogue Ferrum Lek in the temperature range 295–90 K

Abstract

Mossbauer spectra of ferritin and its pharmaceutical analogue Ferrum Lek, both containing nanosized hydrous ferric oxides cores in the forms of ferrihydrite and akaganeite, respectively, were measured in the temperature range 295–90 K. An anomalous line broadening with temperature decrease was observed for ferritin below ~150 K and for Ferrum Lek below ~130 K. Some anomalies were also observed below these temperatures for spectral area and quadrupole splitting.