Line broadening in the 77 K 57Fe-Mössbauer spectra of some ferrous iron-containing medicines

Abstract

We report line broadening in the 77 K 57Fe Mossbauer spectra of some commercially available medicines based on ferrous sulfates and on ferrous fumarates. While introducing only a single ferrous doublet is required to fit the RT spectra of all samples, on the contrary the line shapes of the 77 K spectra are properly described with two ferrous doublets. We discuss eight different static and dynamic hypotheses as possible physical origins for these two doublets, but finally we propose that the reasons are similar for the ferrous sulfates and for the ferrous fumarates containing medicines, and it can be due to the presence of easily dehydrated and hydrated ferrous compounds. The presence of several hydrated sulfates was confirmed by RT Raman spectroscopy. Possible implications of these results related with the hydrated character by which the active parts of the medicines are fabricated by the pharmaceutical companies are also discussed.