Investigation of In Vitro Iontophoresis Facilitated Transdermal Delivery of Glycine

The research presented in this paper discusses the potential of iontophoresis facilitated transdermal delivery of glycine. Iontophoresis has been widely investigated as a noninvasive transdermal drug delivery system. Iontophoresis is the use of a low electric current to carry ionized as well as unionized drug molecules across tissues (like skin) in a noninvasive technique. In the present paper, a custom made low cost, battery powered, portable transdermal iontophoretic system has been investigated for the various parameters of transdermal iontophoretic drug delivery namely drug density in donor formulation, current density, current profile, presence of competitive ions and type of electrode material. In vitro release studies of glycine, as a drug, were done using a modified Franz type glass diffusion cell through excised mouse skin. Factors affecting the delivery of glycine (a non-essential amino acid used to treat schizophrenia, anxiety, insomnia, hypoglycemia etc.) by iontophoresis include concentration of glycine in donor solution, ionic strength of donor solution, density of applied current & its aspect ratio. The change in frequency and electrode type (Ag/AgCl & stainless steel) did not have any significant effect on glycine delivery. In conclusion it could be stated that it is possible to achieve appreciable control over the transdermal delivery of glycine by the low-cost portable iontophoretic drug delivery system developed.