Iontophoretically assisted in vitro membrane transport of nicotine from a hydrogel containing ion exchange resins

The iontophoretically assisted transport of nicotine across artificial and human skin membranes from heterogeneous gel vehicles comprising mixtures of ion exchange resins, to which the nicotine had been bound, and agar hydrogel has been investigated. Both strong and weak resins were used and the effects of resin bead size, the degree of cross-linking in the polymer, the medium in which the drug was bound, the drug concentration and the magnitude of the current were determined. The heterogeneous vehicles were shown to have advantages over comparable simple hydrogel vehicles in their versatility, in their capacities to store the drug and to control both its delivery rate and the pH of the vehicle during iontophoresis. (C) 1998 Elsevier Science B.V. All rights reserved.