Factors influencing drug release characteristic from hydrophilic polymer matrix tablet

Abstract

The aim of this work was to investigate the factors influencing the release characteristics of drug substances from hydrophilic polymer matrix tablet using various hydrophilic polymers such as Polyethylene oxide (PEO), Hydroxyethyl cellulose (HEC) and Xanthan gum (XG). The fabricated tablets were evaluated for physical characteristics like hardness, weight variation, friability and drug content. The effect of addition of diluent, on the drug release was also studied. The swelling studies were conducted for 6 hrs in 0.1 N HCl and phosphate buffer respectively whereas In vitro releases of drug were conducted by buffer change method. All the physical characteristics of the fabricated tablets were found to be within acceptable limits. It was found that the polymers could retard the release of drugs in both simulated gastric fluid (SGF) and simulated intestinal fluid (SIF), but at different levels. Results indicated that drug release characteristics from polymer matrix tablet follow Higuchi square root time kinetics and the mechanism of drug release was diffusion and relaxation.