Mucoadhesive bilayer buccal patches of verapamil hydrochloride: formulation development and characterization

Abstract

Mucoadhesive bilayered buccal patches of VPH were formulated using solvent casting method. Ethyl cellulose and cellulose acetate butyrate were used for backing layer where as hydroxypropylmethyl cellulose (K15M and K100M), polyvinyl alcohol and polyethylene oxide-303 were used for mucoadhesive matrix layer. Combination of hydroxypropylmethyl cellulose K15M with polyvinyl alcohol and polyethylene oxide-303 were used to obtain desired characteristics. Menthol and sodium glycocholate were used as a permeation enhancer and goat buccal mucosa used as model membrane. The patches were evaluated for their characteristics like thickness, tensile strength, percentage elongation, drug content, surface pH, swelling index, ex-vivo residence time, ex-vivo mucoadhesion using texture analyzer, ex-vivo permeation using Franz diffusion cell and in-vitro drug release using USP-23 dissolution apparatus-V with slight modification (paddle-over-disc)