Abstract
The frequency-dependent orientation of human and llama erythrocytes suspended in isotonic solutions and subjected to linearly polarized electric fields is examined. Human erythrocytes may be represented as oblate spheroids (3.9:3.9:1.1 microns) with two distinguishable orientations, while the llama cells are approximated as ellipsoids with three distinct axes (4.0:2.0:1.1 microns). Under appropriate experimental conditions, both orientations of the human cells and all three orientations of the llama cells are observed. A theoretical cell model which accounts for the membrane as a thin confocal layer of ideal capacitance is used to predict the orientational spectra. The predicted spectra compare favorably in frequency range and orientational sequence with experimental data. Estimates for cell internal conductivity and permittivity are obtained by adjusting the values of these important parameters to achieve the closet fit of the theoretical curves to the data. By the use of this method, the internal conductivity of llama erythrocytes is estimated to be 0.26 S/m (+/- 20%), while the effective internal dielectric constant and conductivity of Euglena gracilis are estimated to be 120 (+/- 10%) and 0.43 S/m (+/- 20%), respectively.
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Selected References
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- Ascoli C., Barbi M., Frediani C., Petracchi D. Effects of electromagnetic fields on the motion of Euglena gracilis. Biophys J. 1978 Dec;24(3):601–612. doi: 10.1016/S0006-3495(78)85407-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FRICKE H. Relation of the permitivity of biological cell suspensions to fractional cell volume. Nature. 1953 Oct 17;172(4381):731–732. doi: 10.1038/172731a0. [DOI] [PubMed] [Google Scholar]
- FRICKE H., SCHWAN H. P., LI K., BRYSON V. A dielectric study of the low-conductance surface membrane in E. coli. Nature. 1956 Jan 21;177(4499):134–135. doi: 10.1038/177134a0. [DOI] [PubMed] [Google Scholar]
- Ferris C. D., Griffin J. L. Orientation of Euglena gracilis by electromagnetic fields: theory and experiment. Acta Biol Acad Sci Hung. 1977;28(4):375–387. [PubMed] [Google Scholar]
- Griffin J. L. Orientation of human and avian erythrocytes in radio-frequency fields. Exp Cell Res. 1970 Jul;61(1):113–120. doi: 10.1016/0014-4827(70)90263-6. [DOI] [PubMed] [Google Scholar]
- Griffin J. L., Stowell R. E. Orientation of Euglena by radio-frequency fields. Exp Cell Res. 1966 Nov-Dec;44(2):684–688. doi: 10.1016/0014-4827(66)90487-3. [DOI] [PubMed] [Google Scholar]
- Holzapfel C., Vienken J., Zimmermann U. Rotation of cells in an alternating electric field: theory and experimental proof. J Membr Biol. 1982;67(1):13–26. doi: 10.1007/BF01868644. [DOI] [PubMed] [Google Scholar]
- Iglesias F. J., López M. C., Santamaría C., Domínguez A. Orientation of Schizosaccharomyces POMBE Nonliving Cells under Alternating Uniform and Nonuniform Electric Fields. Biophys J. 1985 Nov;48(5):721–726. doi: 10.1016/S0006-3495(85)83830-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pauly H., Schwan H. P. Dielectric properties and ion mobility in erythrocytes. Biophys J. 1966 Sep;6(5):621–639. doi: 10.1016/S0006-3495(66)86682-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SCHWAN H. P. Electrical properties of tissue and cell suspensions. Adv Biol Med Phys. 1957;5:147–209. doi: 10.1016/b978-1-4832-3111-2.50008-0. [DOI] [PubMed] [Google Scholar]
- Saito M., Schwan H. P., Schwarz G. Response of nonspherical biological particles to alternating electric fields. Biophys J. 1966 May;6(3):313–327. doi: 10.1016/S0006-3495(66)86659-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zimmermann U., Vienken J. Electric field-induced cell-to-cell fusion. J Membr Biol. 1982;67(3):165–182. doi: 10.1007/BF01868659. [DOI] [PubMed] [Google Scholar]