DEVELOPMENT OF SUSTAINED RELEASE TRAMADOL HYDROCHLORIDE BY PELLETIZATION
The aim of the present study was to develop and characterize sustained release pellets of Tramadol HCl using Ethyl cellulose 7cps and Ethyl cellulose 50cps.The pellets were prepared by Wurster process with EC 7cps in 1%w/w, 1.5%w/w and 2%w/w and EC 50cps at 2.5%w/w, 5%w/w and 7.5%w/w. Then the pellets were evaluated for bulk density, angle of repose and Carr’s index. The pellets were characterized for particle size by sieving technology and particle surface, surface texture by SEM analysis. The in-vitro dissolution studies were carried out using 0.1N HCl foe first 2hrs followed by phosphate buffer of pH 6.8 up to 24hrs with USP-II dissolution apparatus. The mean dissolution time was found to be increased by increasing Ethyl cellulose levels. From one way ANOVA it was found that the ratio of binary polymer mixture had significant (p < 0.05) effect on drug release. The data were fitted to various kinetic models. The data fitted well in both Kosermayer (r=0.984) and Hixoncrowl model (r=0.972).The Kosermayer showed n=0.972, confirming the release by non-fickian super case-II kind of drug release.