In vitro penetration of some β-adrenoreceptor blocking drugs through porcine buccal mucosa

Abstract

Some drugs could preferably be administered by using the buccal route. To support the development of a suitable buccal dosage form we designed an in vitro penetration model to investigate drug permeability of the buccal mucosa. Porcine buccal mucosa was excised and clamped inside a two-chambered flow-through diffusion cell. The in vitro penetration of bupranolol, propranolol, oxprenolol and acebutolol was measured in triplicate (PBS-medium, pH 6.8, drug concentration 4 g/l, 37 ° C). The drugs varied in lipophilicity, whereas p K a values were comparable. From the steady-state fluxes, permeability coefficients were calculated. A correlation was found between the permeability coefficient and the drug lipophilicity, which was expressed as the octanol-buffer distribution coefficient. It was concluded that the model is useful for further permeability investigations.