DEVELOPMENT OF CHITOSAN BASED BIOADHESIVE BILAYERED PATCHES OF METOPROLOL TARTARATE

The present study was an attempt to develop bilayered chitosan containing mucoadhesive buccal patches to ensure satisfactory unidirectional release of metoprolol tartarate. Mucoadhesive bilayered buccal patches of metoprolol tartarate were formulated using chitosan as the mucoadhesive polymer and the base matrix for the drug. The impermeable backing layer was of ethyl cellulose to ensure a unidirectional drug release. The patches were evaluated for weight and thickness, content uniformity, surface pH, swelling, invitro drug release, ex vivo mucoadhesive strength, ex vivo mucoadhesion time. The drug release rate from the patches was found to be a function of dose of the drug and PVP K-30 concentration. Incorporation of PVP K-30 improved the patch characteristics with positive effect on swelling and drug release in increased concentration. Patches containing lower drug concentration had higher bioadhesive strength with extended drug release. Stability studies were conducted in simulated saliva and it was found that both drug and the patches were stable. The bilayered buccal patches of metoprolol tartarate can be formulated using chitosan as the mucoadhesive polymer to obtain satisfactory unidirectional drug release with adequate mucoadhesion.