Iontophoresis transport mechanism

Pikal, M.J., and S. Shah. 1990. Transport mechanisms in iontophoresis. II. Electroosmotic flow and transference number measurement for hairless mouse skin. Pharm Res 1 (3) 213. 

Pikal, M. J. (1990). Transport mechanisms in iontophoresis. I. A theoretical model for the effect of electroosmotic flow on flux enhancement in transdermal iontophoresis. Pharm. Res. 7 118-126. 

Pikal, M. and Shah, S. Transport mechanisms in iontophoresis III. An experimental study of the contributions of electro-osmotic flow and permeability change in transport of low and high MW solutes. Pharm. Res. 7 222, 1990. Gangerosa, L. P., Park, N.-H., Wiggins, C. A., and Hill, J. M. Increased penetration of non-electrolytes into mouse skin during iontophoretic water transport (lontohydrokinesis). J. Pharm. Exp. Ther. 212 311, 1980. 

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],... 

In addition to solute structure, a number of factors affecting iontophoretic transport need to be gained for the development of useful optimal iontophoretic drug delivery systems. These include the behavior of solute ions in solution during iontophoresis, mechanisms of solute ion transport through the skin, the effect of different power sources, the choice of electrodes, the composition of vehicles, and the influence of other ions present in the process of drug delivery. 

Bhatia, K. S. and Singh J. (1998a). Mechanism of transport enhancement of LHRH through porcine epidermis by terpenes and iontophoresis permeability and lipid extraction studies, Pharm Res., 15 1857-1862. 

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