Mössbauer spectroscopy of human liver ferritin and its analogue, Ferrum Lek, in the temperature range of 295-90 K: Comparison within the homogeneous iron core model

Abstract

Human liver ferritin and its pharmaceutical analogue, Ferrum Lek, containing nanosized hydrous ferric oxides cores in the forms of ferrihydrite and akaganéite, respectively, were studied using Mössbauer spectroscopy with a high velocity resolution in the temperature range of 295-90 K. To simplify comparison, these spectra were fitted using one quadrupole doublet within the homogeneous iron core model. An unusual line broadening with a temperature decrease was observed in this way for human liver 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. The Debye temperature for both iron cores was evaluated from temperature dependence of isomer shift using the temperature dependence of the secondorder Doppler shift.

Mössbauer Spectroscopy with a High Velocity Resolution in the Studies of Nanomaterials

“…Nevertheless, application of the first rough model in [ 45 , 46 , 47 ] permitted us to observe the features in the temperature dependencies of some parameters and to estimate the Mössbauer temperature Θ M (see [ 23 ]) for ferritin within the Debye model by measuring the second order Doppler shift δ SOD and using equation: where m is the mass of Fe atom, k is the Boltzmann constant, c is the speed of light, and x = ħ ω/ kT (ω being frequency of vibrations).…”

“…Samples of iron–polymaltose complexes Ferrum Lek, Maltofer ® and Ferrifol ® prepared by manufacturers as tablets were studied by Mössbauer spectroscopy with a high velocity resolution in the temperature range 295–90 K [ 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ]. These spectra show the paramagnetic two-peak shape with non-Lorentzian lines.…”