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Cited by 614

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Magnetite biomineralization in the human brain.

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Kirschvink, J L, Kobayashi-Kirschvink, A, Woodford, B J·1992·Proceedings of the National Academy of Sciences

Abstract

Although the mineral magnetite (Fe3O4) is precipitated biochemically by bacteria, protists, and a variety of animals, it has not been documented previously in human tissue. Using an ultrasensitive superconducting magnetometer in a clean-lab environment, we have detected the presence of ferromagnetic material in a variety of tissues from the human brain. Magnetic particle extracts from solubilized brain tissues examined with high-resolution transmission electron microscopy, electron diffraction, and elemental analyses identify minerals in the magnetite-maghemite family, with many of the crystal morphologies and structures resembling strongly those precipitated by magnetotactic bacteria and fish. These magnetic and high-resolution transmission electron microscopy measurements imply the presence of a minimum of 5 million single-domain crystals per gram for most tissues in the brain and greater than 100 million crystals per gram for pia and dura. Magnetic property data indicate the crystals are in clumps of between 50 and 100 particles. Biogenic magnetite in the human brain may account for high-field saturation effects observed in the T1 and T2 values of magnetic resonance imaging and, perhaps, for a variety of biological effects of low-frequency magnetic fields.

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Metadata

Authors
Kirschvink, J. L., Kobayashi-Kirschvink, A., & Woodford, B. J.
Venue
Proceedings of the National Academy of Sciences
Published
1992-08-15
Volume
89
Issue
16
Pages
7683-7687
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
OpenAlex
W2004587610
Cited by
614
References
1
FWCI
5.47
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: Magnetite biomineralization in the human brain. https://app.cochat.ai/papers/10.1073/pnas.89.16.7683
The paper
Kirschvink, J. L., Kobayashi-Kirschvink, A., & Woodford, B. J. (1992). Magnetite biomineralization in the human brain. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.89.16.7683

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

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