Electroporation electroosmosis

Iontophoresis by definition is the process of transport of ions into or through a tissue by the use of an applied potential difference across the tissue [52], Depending on the physicochemical characteristics of a molecular species, electrorepulsion is usually the primary mechanism of transdermal transport for ions, whereas electroosmosis and increased passive diffusion (as a result of the reduced barrier properties) are more prominent for neutral species [53]. In contrast, enhancement in flux for neutral or weakly charged species during electroporation arises predominantly from the reduced barrier properties of the membrane, whereas direct electrorepulsion is usually of secondary importance [25],... 

Cell lysis under a high electric field is referred to as electroporation [6], Under these conditions, the cell membrane experiences dramatic changes in permeability to macromolecules. The main applications of the electroporation include the electrotransformation of cells and the electroporative gene transfer by the uptake of foreign DNA or RNA (in plants, animals, bacteria, and yeast). The electric field generates permeable microspores at the cell membrane, so that the nucleic acid can be introduced by electroosmosis or diffusion. 

The term iontophoresis encompasses several processes for moving molecules across the skin electromigration, electroosmosis, and electroporation. Electromigration is the movement of charged ionic species in response to an applied electric field. This process is usually of... 

About 10 years ago, a new, easy and versatile technique for the introduction of larger macromolecules into eukaryotic and prokaryotic cells was established (Neumann et al., 1982 Knight, 1981) it is now commonly known as electroporation (Weaver, 1993). It is mainly a physical process, based on the transient permeabiliza-tion of cell membranes by pulses of sufficiently high electric fields. The underlying membrane phenomenon, called reversible electrical breakdown (REB) followed by transient pore formation, occurs if the transmembrane potential reaches values of 0.5 -1.5 V. Membrane pores are generated and molecules are transported through these pores by diffusion, electrical drift, and electroosmosis. Electroporation seems to be a rather universal process in most natural membranes. 

---