Abstract:
:Despite the importance of magnetic properties of biological samples for biomagnetism and related fields, the exact magnetic susceptibilities of most biological samples in their physiological conditions are still unknown. Here we used superconducting quantum interferometer device to detect the magnetic properties of nonfixed, nondehydrated live cell and cellular fractions at a physiological temperature of 37°C (310 K). It is obvious that there are paramagnetic components within human nasopharyngeal carcinoma CNE-2Z cells. More importantly, the magnetic properties of the cytoplasm and nucleus are different. Although within a single cell, the magnetic susceptibility difference between cellular fractions (nucleus and cytoplasm) could only cause ∼41-130 pN forces to the nucleus by gradient ultrahigh magnetic fields of 13.1-23.5 T (92-160 T/m), these forces are enough to cause a relative position shift of the nucleus within the cell. This not only demonstrates the importance of magnetic susceptibility in the biological effects of magnetic field but also illustrates the potential application of high magnetic fields in biomedicine.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Tao Q,Zhang L,Han X,Chen H,Ji X,Zhang Xdoi
10.1016/j.bpj.2019.12.020subject
Has Abstractpub_date
2020-02-04 00:00:00pages
578-585issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(19)34405-4journal_volume
118pub_type
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