Abstract

DEVELOPMENT OF pH-INDEPENDENT CONTROLLED RELEASE MATRIX TABLETS OF PROPRANOLOL HCL

V. Kamalakannan*, P. Meenaprabha and R. Sambathkumar

Abstract

In the present study, a pH-independent controlled release matrix system for acidic drugs was designed by incorporating releasemodifiers in the formulation. Controlled release matrix tablets were prepared by compression of Propranolol hydrochloride. This study was to overcome pH -dependent release of weakly basic drug and to achieve pH independent drug release. An anti -hypertensive drug, Propranolol hydrochloride was chosen due to its pH -dependent solubility. One of the approaches to solve the problem of pH - dependent release of weakly basic drug has been done in this work. The water soluble and highly swellable HPMC was used as a matrix former and organic acids maleic acid, Succinic acid and fumaric acid were added to the drug polymer system in different formulations in varying proportions (at 10, 20, 40 and 80mg) as release modifiers. The addition of organic acids was found to maintain an acidic micro environmental pH inside the polymer matrices during drug release in phosphate buffer pH 7.4. On the other hand, the amount of each organic acid added to the system had no effect on the drug release in acidic solution 0.1N HCl. So the micro Environmental conditions for the dissolution and diffusion of drug were almost kept constant. Thus, the release of Propranolol hydrochloride from tablets containing HPMC and organic acids was found to be pH -Independent. Between the two organic acids, Succinic acid showed slightly better release when compared to Citric acid.

Keywords: pH-independent, Propranolol hydrochloride, HPMC, controlled release systems.