Abstract

Drug release from matrix dosage form is affected by polymer swelling, it’s erosion, drug distribution inside the matrix and
polymeric combination. To prepare buccal controlled release patches hydrophilic, swellable, porous polymeric material
alone or in optimum combination along with their buccoadhesive strength is essential. Here a plant derived gum like Gum
karaya (GK) , a cellulose derivative-HPMCK15M and Polyox have been used to prepare buccal buccal patches of Carvedilol
phosphate . The effect of Polyox and gum karaya on the release kinetics of drug from the buccal patches have been
studied.The buccal patches were evaluated for it’s physico-mechanical characteristics. The buccal patches revealed
satisfactory physic-mechanical results. Buccoadhesive strength was found to be in the range of 31-35 gm, which is good
enough to hold the buccal buccal patches inside the buccal cavity. Percent Swelling of the buccal patches were in the range
of 449-529%.Swelling is maximum in the buccal patches where Polyox is present along with HPMCK15M and GK. Drug
dissolution from the buccal patches has been described by kinetic models. The release data were fitted in different kinetic
models, like zero order, first order and Higuchi. Release study of Buccal patches made up of only HPMCK15M followed
zero order kinetics.. Buccal patches with GK along with HPMCK15M provided Higuchi kinetics over 8 hours of drug
release.Further incorporating Polyox along with HPMCK15M and GK showed mixed order kinetics. Initially drug release
followed Higuchi kinetics followed by zero order in the last phase.

Key words: Gum karaya, HPMCK15M, Polyox, Release kinetics, Buccoadhesive strength