Influence of Formulation Variables on the in Vitro Dissolution of Gum Damar Based Matrix Tablets

The objective of the study was to examine the influence of two variables, concentration of the matrixing agent and diluent on the release of diclofenac sodium from hydrophobic matrix tablets. A 32 full factorial design was employed to optimize drug release profile. Concentration of the hydrophobic matrixing agent (X1) and type of diluent (X2) were taken as independent variables. The dependent variables selected were percentage drug release at 3h, 6h, 9h, time required for 50% drug release and zero order rate constant. Matrix tablets were evaluated for hardness, friability, weight variation and in vitro drug release. Polynomial equations and response surface plots were generated for all dependent variables. It was observed that all the factors had significant contribution on all dependent variables. INTRODUCTION: Oral route of administration has been received more attention in the pharmaceutical field because of the more flexibility in the designing of dosage form than drug delivery design for other routes . In pharmaceutical CRDDS, matrix based systems are the most commonly used type of release controlling methodology owing to their simple manufacturing process, level of reproducibility, stability of the raw materials and dosage forms as well as ease of up operation and also resistant to dose dumping. These systems improve patient compliance and decreased adverse drug reactions . Natural gums are promising biodegradable polymeric materials. The fact for increase in importance of natural plant based material is that plant resources are renewable and if cultivated or harvested in a sustainable manner, they can provide a constant supply of raw materials . Many natural polymeric materials have been successfully used in sustainedrelease tablets. Gum damar is a hard resin collected by tapping trees from Shorea spp. (including S. javanica, S. lamellata, S. retinodes), Dipterocarpaceae from South-East Asia, including Malay & Indonesian archipelagos. Damar gum is a triterpenoids resin, containing a large number of triterpenes and their oxidation products. Many of them are low molecular weight compounds (Dammarane, Dammarenolic acid, Oleanane, Oleanonic acid, etc), but dammar also contains a polymeric fraction, composed of polycadinene. Their main use is in the manufacture of paper or wood varnishes and lacquers, particularly as a varnish for the fine art, and some paints. Correspondence to Author: