Electroosmotic flow as a result of buccal iontophoresis – Buccal mucosa properties

The objective of this study was to investigate and to better understand the properties of buccal mucosa as a semipermeable membrane and a portal for drug administration by iontophoretic and electroosmotic means. In vitro experiments showed that buccal mucosa at the pH of about 7.4 behaved as a cation-exchange membrane and non-linear resistor. It had lower resistance and was more permeable for water than a skin. The electroosmotic volume flow through mucosa depended on current density, mucosa resistance and electrolyte concentration. Sodium dodecyl sulfate (in concentration range 0.001–0.005 mol L−1) and urea (in concentration range 0.42–1.67 mol L−1) did not promote a water transfer through buccal mucosa, however, both substances enhanced flow through the skin.