Volume :
1
Issue :
1
Abstract :
Extended release drug delivery system have started gaining popularity and acceptance as new drug delivery system due to better control over release for extended time providing convenience of drug administration. Keeping in view economy of the process and simplicity involved in design, this study was undertaken to develop extended release tablets of Diltiazem using different hydrophobic polymers by melt granulation technique. Based on Preformulation studies the concentrations of the hydrophobic polymers to be used in the formulation were optimized. The compatibility between the pure drug and excipients used in design of the formulations were confirmed by IR studies. Hydrophobic polymers namely Compritol ATO 888 and Hydrogenated castor oil were used to formulate six different formulations. Other excipients used were of directly compressible grade. Aerosil used as a glidant. Lactose used as a diluent in the formulation. Extended release tablets were formulated using melt granulation technique. The tablets were then evaluated for their shapes, color, thickness, friability, weight variation, drug content and In-vitro dissolution studies. Drug release is inversely proportional to the level of rate retarding polymer present in matrix system i.e. extent of retardation of drug release increases with decrease in polymer content of the matrix. Hydrogenated castor oil was found to be a good retardant since it forms thin coating on surface of drug particle. Drug release from matrix is primarily controlled by diffusion process. This process seems to be governed by amount of hydrophobic polymer. Higher the amount of hydrophobic polymer tends to show diffusion controlled release of drug.