Evaluation of the Debye temperature for iron cores in human liver ferritin and its pharmaceutical analogue, Ferrum Lek, using Mössbauer spectroscopy

An iron–polymaltose complex, Ferrum Lek, used as antianemic drug and considered as a ferritin analogue and human liver ferritin were investigated in the temperature range of 295–90 K using 57Fe Mössbauer spectroscopy with a high velocity resolution (in 4096 channels). This study aimed to make a comparison of the Fe atom dynamics in the Ferrum Lek and ferritin iron cores by means of evaluation of the Debye temperature using the temperature dependence of the spectral center shift obtained with two different fitting procedures and the second order Doppler shift approach. The Debye temperature, evaluated as ΘD = 502 ± 24 K for Ferrum Lek and ΘD = 461 ± 16 K for human liver ferritin, demonstrated a very small difference in the Fe atom vibrations, reflecting a slightly smaller rigidity in the iron cores in human liver ferritin.

Mössbauer spectra of the human liver ferritin and of Ferrum Lek, and values of the Debye temperature, ΘD, as determined from a temperature dependence of the center shift.Figure optionsDownload as PowerPoint slide