Abstract

EVALUATION OF ALBIZIA GUM IN THE FORMULATION OF CONTROLLED RELEASE MATRIX TABLETS USING LOSARTAN POTASSIUM

P. Eswaramma* and K. V. Ramana Murthy

ABSTRACT

Matrix tablets were developed using albizia gum for investigating it‟s suitability for the controlled release using losartan potassium as a model drug. Tablets were prepared by direct compression method. Lactose and dibasic calcium phosphate (DCP) were used as channeling agents. In vitro studies were performed in 0.1 N HCl for the first two hours and pH 6.8 phosphate buffer for the next ten hours. Concentration of gum and nature of diluents influence the retardation of drug release. The drug release was retarded when compared with dissolution patterns of synthetic polymers like poly ethylene oxide (PEO 303) and poly vinyl alcohol (22-30 cps). The release rate, extent and mechanisms were found to be governed by the concentration of the gum and channelling agents. Increased rate and extent of the drug release were found by using higher content of channelling agent in the matrix due to increased porosity. It was found that type and concentration of channelling agent significantly affect the percentage drug release, release rate constant (K) and diffusion exponent (n). The FTIR and DSC studies confirmed that there was no interaction between the drug and albizia gum.

Keywords: Losartan potassium, albizia gum, controlled release matrix tablets, poly ethylene oxide, poly vinyl alcohol, lactose and dibasic calcium phosphate.