In Vitro Artificial Membrane-Natural Mucosa Correlation of Carvedilol Buccal Delivery

Development and evaluation of buccal formulations is highly challenging and requires lengthy permeation studies. In vitro studies include preparation of freshly excised mucosa from sacrificed animals that should be immediately employed to test permeation. In addition, inconsistent permeability results arise due to variations in tissue preparation. A simple and rapid method for in vitro evaluation is required to overcome erratic results, save on animals, and accelerate the development process of buccal products. The current work investigated the use of model polymeric membranes; cellulose acetate and cellulose acetate-nitrate, as rapid-screening alternative to the natural mucosa. Permeability coefficient and steady-state flux for carvedilol, a model hydrophobic drug, were determined in natural and artificial membranes. The effect of chemical enhancers on permeability through polymeric membranes was measured and compared against that in porcine and rabbit mucosa. A strong and statistically significant correlation between artificial membranes and buccal mucosa for the delivery of carvedilol was established.