Biological/Medical pulsed electric field treatments

The application of electric fields to a medium, which contains biological cells, causes build-up of charges at the cell membrane, and consequently a change in the transmembrane potential of cells. For low electric fields, this causes voltage-gating, the voltage-induced opening of channels in the cell membrane. With increasing electric field, at transmembrane voltages on the order of 1 V, the cell membrane becomes permeable, ail effect called electroporation. It is reversible for moderate electric fields (kV/cm) and pulse duration of microseconds to milliseconds. At higher fields and/or longer pulse durations the cells will be lysed. Applications of these outer membrane effects are biofouling prevention, medical applications such as electroporative: delivery of chemotherapeutic drugs into tumor cells, gene therapy, transdermal drug delivery, and bacterial decontamination of drinking water and liquid food. A new type of field-cell interaction, "intracellular electromanipulation" by means of submicrosecond electrical pulses at electric fields exceeding 50 kV/cm has been recently added to known cellular bioelectric effects. The bioelectric technique, which is based on high frequency field-cell interactions, extends electroporation of the outer cell membrane to subcellular structures.