Ac-field-induced KCl leakage from human red cells at low ionic strengths

Georgiewa, R.; Donath, Edwin; Gimsa, Jan; Löwe, U.; Gläser, Roland

doi:10.1016/0302-4598(89)87044-8

Cited by 14 publications

(7 citation statements)

References 21 publications

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“…RBC membranes are for the most part nonconducting (s 5 1 mS/m) [52,[54][55][56][57] and contribute significantly to the classification of erythrocytes being dielectrics -an object or material of low electrical conductivity [14,54]. In contrast, erythrocyte interiors are more conductive (s 5 0.53 S/m) [25,58,59] and vary due to hemoglobin, other cytoplasm molecules, and organelles [25,27,60]. The biconcave shape and structure variation typical of RBCs, as well as their dependence on solvent conditions, pH, tonicity, and temperature have all added complications to dielectric force calculations [15,40].…”

Section: Polarization and Dispersion Mechanismsmentioning

confidence: 95%

Manipulation and characterization of red blood cells with alternating current fields in microdevices

et al. 2003

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The motion of a suspension of erythrocytes (red blood cells, RBCs) in response to a high-frequency alternating current (AC) field in a microfluidic device is examined with parallel and orthogonal electrode configurations to delineate the various fundamental driving forces. Cell repulsion from the platinum electrodes due to electrode polarization interacting with cell membrane polarizations is observed to be the strongest force acting on the particles in the first few seconds of field application. We exploit this strong repulsion to concentrate the bioparticles between the microelectrodes to amplify multiparticle aggregation phenomenon and dielectrophoretic (DEP) manipulation in a small and well-characterized region within the microfluidic device. Secondary motions include RBC pearl chain formation along field lines due to particle polarization followed by classical dielectrophoretic motion of the chains across field lines to regions of weaker field. These are driven by far weaker dipole-dipole and field-dipole interactions than the preliminary electrode repulsions. RBC chain length and total aggregated cells are presented for a variety of AC frequencies and are significantly amplified by the electrode repulsion. Motion of particles away from the polarized electrode is found to be species- and age-sensitive and can stand by itself as a promising identification and separation mechanism. In a 0.1 S/m isotonic phosphate buffer saline medium, we observe the largest cell mobilities at an optimal frequency of approximately 1 MHz, corresponding to the inverse diffusion time across the double layer of the cell and across the electrode's polarized layer. This suggests that the dielectric responses of both particles and electrodes in the low MHz frequency range are mostly determined by normal electromigration of ions from the bulk to their interfaces. Sensitivity to RBC age and species suggests that the surface proteins and membrane ion channels can affect the capacitance of the interface to accommodate the ions from the bulk. Such surface ion accumulation and polarization mechanisms are different from the classical dielectric theories. The resonant frequency of electrode polarization at around 1 MHz falls between positive and negative dielectrophoretic resonant frequency peaks - suggesting that the double-layer polarization mechanism is a distinct and potentially important bioparticle manipulation tool.

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Section: Polarization and Dispersion Mechanismsmentioning

confidence: 95%

Manipulation and characterization of red blood cells with alternating current fields in microdevices

et al. 2003

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“…When erythrocytes are suspended in media which differ from that of the physiological state (1.48 S m -1 ), rapid cell volume changes were observed ( Fig 2A ). Lightly buffered NaCl [ 13 ] was deliberately chosen as the suspending electrolyte for the present study because Na + and Cl - are the dominant ions present blood plasma and so NaCl was the simplest system in which to study cell volume changes in HRBC and is the electrolyte of choice for such studies [ 4 , 17 , 21 , 22 , 40 , 41 , 50 , 51 ] although the role of K + should not be overlooked [ 52 , 53 ]. The time course of experiments in the present study were very short (5 minutes) which would not have allowed much time for substantial leakage of K + or other ions.…”

Section: Discussionmentioning

confidence: 99%

Influence of Na+ disorder on cytoplasmic conductivity and cellular electromagnetic (EM) energy absorption of human erythrocytes (PONE-D-21-36089)

Sudsiri

Ritchie

2023

PLoS ONE

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Cytoplasmic conductivity of human erythrocytes may be significantly disturbed by the composition of the external suspending media. Effects of external NaCl on cytoplasmic conductivity of human erythrocyte (Human Red Blood Cells, HRBC) were investigated in a simple NaCl system. Using thermodynamic theory cytoplasmic conductivities could be calculated from internal [K+], [Na+], [Cl-] and [HCO3-]. Effect of cell volume and cell water changes were introduced and allowed for using the Debye-Hückel-Onsager relation and Walden’s rule of viscosity. Cell volume and cell water change of HRBCs were measured in suspending isotonic solutions with conductivities from 0.50 S m-1 up to hypertonic solutions of conductivity of 2.02 S m-1 at selected temperatures of 25°C (standard benchmark temperature) and 37°C (physiological temperature). In isotonic solutions, cytoplasmic conductivity of human erythrocyte decreases with rise in the external media ionic concentration and vice versa for hypertonic solutions. The HRBC is capable of rapidly regulating its volume (and shape) over quite a wide range of osmolality. Specific Absorption Rate (SAR, 900 MHz) values (W kg-1) of electromagnetic radiation are below safe limits at non-physiological 25°C but above legal limits at 37°C [National Council on Radiation Protection and Measurements, NCRP]. However, at 37°C under both hypertonic [Na+] and isotonic but low [Na+], SAR increases further beyond legal limits.

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“…Studies have shown that the extracellular pH of normal cells is alkaline, ranging from 7.2 to 7.4, whereas the extracellular pH of cancer cells is significantly more acidic, 6.2–6.9, which is caused by aerobic glycolysis. − However, contrary to our initial presumptions, the intracellular pH of cancer and normal cells reported in the literature is very close (pH i ≈ 7.2). , Contrary to solid tumors, the reversed transmembrane [H + ] distribution (acidic extracellularly/alkaline intracellularly) is not commonly observed in tissue. Cells particularly respond to LCB by pumping out ions followed by shape regulation, and after awhile, they die. , Therefore, there is a critical necessity to consider the time-dependent dielectric response of cancer cells low-conductivity buffers. ,,, …”

Section: Buffer Solutions For Manipulation and Characterization Of Ca...mentioning

confidence: 99%

“…Cells particularly respond to LCB by pumping out ions followed by shape regulation, and after awhile, they die. 97,161 Therefore, there is a critical necessity to consider the time-dependent dielectric response of cancer cells low-conductivity buffers. 45,150,155,162 Considering the aspects mentioned above, we will further discuss below some of the buffer solutions commonly identified in the literature for trapping and characterizing from an electrical viewpoint the cancer cells.…”

Section: ■ Theoretical Considerationsmentioning

confidence: 99%

Dielectrophoretic Manipulation of Cancer Cells and Their Electrical Characterization

Turcan

Olariu

2020

ACS Comb. Sci.

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Electromanipulation and electrical characterization of cancerous cells is becoming a topic of high interest as the results reported to date demonstrate a good differentiation among various types of cells from an electrical viewpoint. Dielectrophoresis and broadband dielectric spectroscopy are complementary tools for sorting, identification, and characterization of malignant cells and were successfully used on both primary tumor cells and culture cells as well. However, the literature is presenting a plethora of studies with respect to electrical evaluation of these type of cells, and this review is reporting a collection of information regarding the functioning principles of different types of dielectrophoresis setups, theory of cancer cell polarization, and electrical investigation (including here the polarization mechanisms). The interpretation of electrical characteristics against frequency is discussed with respect to interfacial/Maxwell−Wagner polarization and the parasitic influence of electrode polarization. Moreover, the electrical equivalent circuits specific to biological cells polarizations are discussed for a good understanding of the cells' morphology influence. The review also focuses on advantages of specific low-conductivity buffers employed currently for improving the efficiency of dielectrophoresis and provides a set of synthesized data from the literature highlighting clear differentiation between the crossover frequencies of different cancerous cells.

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Ac-field-induced KCl leakage from human red cells at low ionic strengths

Cited by 14 publications

References 21 publications

Manipulation and characterization of red blood cells with alternating current fields in microdevices

Manipulation and characterization of red blood cells with alternating current fields in microdevices

Influence of Na+ disorder on cytoplasmic conductivity and cellular electromagnetic (EM) energy absorption of human erythrocytes (PONE-D-21-36089)

Dielectrophoretic Manipulation of Cancer Cells and Their Electrical Characterization

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