Design and Characterization of Carbopol-HPMC-Ethyl Cellulose based Buccal Compact containing Propranolol HCl

Abstract:

The purpose of this work was to evaluate the effect of formulation variables on release properties and bioadhesive strength in development of three layered buccal compact containing highly water-soluble drug propranolol hydrochloride (PRPH). Formulations were prepared based on rotatable central composite design with peripheral layer polymer ratio (carbopol 934P: HPMC 4KM) and core layer polymer ratio (HPMC 4KM: sodium alginate) as two independent formulation variables. The three layered buccal compact comprises a peripheral layer, core layer and backing layer. In order to provide the unidirectional drug release towards the mucosa and avoid backward diffusion, ethyl cellulose (EC) and magnesium stearate were included as backing layer. The dependent (response) variables were considered: bioadhesion force, and percentage PRPH release at 8 h. The decrease in PRPH release was observed with an increase in both the formulation variables and as the carbopol: HPMC ratio increases the bioadhesive strength also increases. The desirability function was used to optimize the response variables, each having a different target and the observed responses were highly agreed with experimental values. The results demonstrate the feasibility of the model in the development of three layered buccal compact containing highly watersoluble drug propranolol hydrochloride.

Key words: Bioadhesive strength, Buccal compact, Backing layer, Peripheral layer.