A Mössbauer spectrometry study of iron in hepatic and splenic tissues. Preliminary results

Ferritin, mammalian iron reserve protein, is made of a ferric hydroxide core enclosed in a protein shell. Several Mossbauer spectrometry studies have been carried out on ferritin molecules extracted from horse spleen. They demonstrate the existence of superparamagnetic properties in the iron core and the coming out of a nuclear Zeeman effect, characteristic of a magnetic order, below 40-30 K temperatures. Among the organs and tissues of the boby, the liver and spleen usually rank highest in iron content, mainly as ferritin and hemosiderin. In the present work, Mossbauer spectra of lyophylized samples of liver and spleen from horse, beef and calf have been recorded at room, liquid nitrogen and liquid helium temperature. In accordance with the previous works we find for the lyophylized horse spleen samples, the spectra at 4.2 K are mainly characterized by a Zeeman effect of the iron nucleus. On the other hand, in lyophylized samples of horse liver, even at liquid helium temperature, a doublet corresponding to Fe3+ is observed, in addition to the Zeeman sextuplet, representing an important fraction of the Mossbauer spectrum.