In:
Journal of Applied Physics, AIP Publishing, Vol. 41, No. 3 ( 1970-03-01), p. 1002-1002
Abstract:
The function of ferritin is to stock the iron present in the body. Ferritin consists of a protein shell surrounding a core which is mainly an iron hydroxide FeOOH. Mössbauer effect and magnetic measurements in the temperature range 2°–300°K show ferritin to be superantiferromagnetic with grains 70 Å in diameter. This condition is characterized by a blocking temperature and a thermoremanent magnetization. The magnetic moment of each grain is about 1.2 × 10−18 emu and the surface anisotropy is 5.8 × 10−2 erg/cm2. In aqueous solution, ferritin retains its magnetic properties apart from a slight modification due to the penetration of water which expands the grains. Ferritin can contain up to a maximum of 23 wt% iron without any profound effect on the basic magnetic properties. High pulse field experiments (175 kOe) show ferritin to behave as a metamagnet with a threshold field of 75 kOe. The core of the molecule has hexagonal crystal structure with a = 11.79 Å and c = 9.90 Å, resembling the planar compact structure of oxygen in δ-FeOOH. The iron atoms are situated on the tetrahedral and octahedral sites of the lattice. Some of this work has been published elsewhere: A. Blaise, J. Chappert, and J. L. Girardet, Compt. Rend. 261, 2310 (1965); A. Blaise, J. Feron, J. L. Girardet, and J. J. Lawrence, Compt. Rend. 265, 1077 (1967); J. L. Girardet and J. J. Lawrence, Bull. Soc. Franc. Mineral. Crist. 91, 440 (1968).
Type of Medium:
Online Resource
ISSN:
0021-8979
,
1089-7550
Language:
English
Publisher:
AIP Publishing
Publication Date:
1970
detail.hit.zdb_id:
220641-9
detail.hit.zdb_id:
3112-4
detail.hit.zdb_id:
1476463-5
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