Magnetometric diagnostics of ferritin in living matter

Investigations in a broad sample set of living matter, including plants and silty soil fractions from various climate and soil zones, microorganisms, and muscle tissues of birds and mammals (a total of about 200 samples) show that iron in native substances occurs in the form of nanodimensional particles of hydroxide (ferrihydrite). Based on the data of Mössbauer spectroscopy and magnetic measurements, these nanoparticles can be identified as nuclei of the globular protein ferritin. Most measurements were performed at 290 K (i.e., without using cryogenic techniques).