Electroporation
Electroporation is a temporary condition of the outer membrane of blood cells becoming "porous" as a result of high electric fields causing 1/2 to 1 volt across each of the cells. While the cells are porous, normally unwanted fluid & substances can enter into the blood cell with resultant disturbing effects. This man-made effect is useful to scientists though, which is why there are companies like Genetronics which manufacture laboratory instruments which induce electroporation. It should be a great relief to all to know that these blood electrification devices do not produce an effect so extreme as electroporation. Brian Austin, Technical Support Manager at Genetronics (an electroporation device company), emailed me concerning Beck blood electrifiers that "with the (electrical) conditions used, there should be no electroporation effects. Field strengths are not high enough." J. C. Weaver of the Massachusetts Institute of Technology in his report on electroporation published in the Journal of Cellular Biochemistry (51:426-435 1993) reported "In the case of isolated cells, mammalian cells experience electroporation for electric fields of about E=1kv/cm (1000 volts with a distance of 1 centimeter between electrodes) for short pulses." Another electroporation device manufacturer, Cyto Pulse Sciences, stated on their website (in the equipment tutorial) that red blood cells need 1430 volts per centimeter for electroporation. The research paper "Microfluidic electroporation of tumor and blood cells: observation of nucleus expansion and implications on selective analysis and purging of circulating tumor cells"
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2872780/ stated that
"With the electroporation duration of 100–300 ms, the threshold for irreversible electroporation (or electric lysis) is ~300–100 V/cm-1 for M109 tumor cells and ~ 1100–1200 V/cm-1 for RBCs [red blood cells]. WBCs [white blood cells] presented a low threshold of 400–500 V/cm-1." [V/cm-1 refers to the voltage per .1cm electrode spacing which is per millimeter. 300ms equals .3 seconds. This is the maximum exposure to electricity they use because otherwise the electricity would overheat the cells if more time was used.]
Typically, 10,000-100,000 V/cm (varying with cell size) in a pulse lasting a few microseconds to a millisecond is necessary for electroporation. This electric pulse disturbs the phospholipid bilayer of the membrane and causes the formation of temporary aqueous pores. The electric potential across the membrane of the cell simultaneously rises by about 0.5-1.0 volts so that charged molecules (such as DNA) are driven across the membrane through the pores in a manner similar to electrophoresis.
http://www.bio.davidson.edu/Courses/Molbio/MolStudents/spring2003/McCord/electroporation.htm
Wikipedia on electroporation: "It is generally accepted that for a given pulse duration and shape, a specific transmembrane voltage threshold exists for the manifestation of the electroporation phenomenon (from 0.5 V to 1 V)."
"Transmembrane", in context of talking about a cell, means "across the cell membrane" which basically means from one side of the cell to the other. So when the electroporation papers say around 1 volt transmembrane voltage is needed they are saying each cell in a culture needs that voltage. Let's say the cell culture has a cell density that provides 1,000 cells linearly between the electroporators electrodes. 1,000 volts would need to be provided to produce 1v transmembrane voltage.
Wikipedia, on "red blood cell", says "women have about 4 to 5 million per microliter (cubic millimeter) of blood and men about 5 to 6 million". That gives a linear density of almost 170. (What I mean is that there would be 170 cells in one line from one side to the other of that cubic millimeter.) From hand to hand the arteries have a distance around 1600 millimeters. So the linear density of red blood cells from hand to hand is 1600x170 which is 272,000. Applying 30 volts from an electromedicine device means each red blood cell will have 30/272,000 volts which is .00011 volts each. This is about 10,000 times too weak to cause electroporation.
http://medical-dictionary.thefreedictionary.com/electroporation
"electroporation: the use of high-voltage electrical impulse to create pores through a cell membrane and allow uptake of DNA into a cell."
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