Modification of Mechanism of Drug Release from Processed Hydrogenated Vegetable Oil

R T J Chigwanda; J N Staniforth

R T J Chigwanda Department of Pharmacy, Faculty of Medicine, University of Zimbabwe, P.O. Box MP 167, Mt Pleasant, Zimbabwe
J N Staniforth Ventura Ltd, University of Bath, Claverton Down Rd, BA2 7A Y, Bath, UK

Keywords: Processed hydrogenated vegetable oil; coupled with relaxation; Myverol

Abstract

This study was aimed at altering the mechanism of drug release from processed hydrogenated vegetable oil from its predominant square root of time kinetics since release rate decreases with time due to the longer distance that the drug in the inner layers has to travel before eluting out. A variety of materials were incorporated into the oil so as to alter the release profile. The release from the various modified matrices was analysed.
Myverol, mainly glycerol monostearate, was found to alter drug release from processed hydrogenated vegetable oil matrices from Higuchi model type kinetics to Fickian diffusion coupled with relaxation model type kinetics. This occurred at a myverol concentration of 30% w/w. This change in release kinetics was attributed to the surfactact effects of myverol that weakened the hydrogenated vegetable oil matrix. A diffusion-relaxation controlled release system with appropriate lag times could be targeted to the various parts of the gastrointestinal tract.