Model Based Approach to Study of Release Kinetics of the Drug Chlorhexidine from Hydrogels

Abstract Knowledge of the release kinetics together with its (mathematical) model is inevitable for prediction of properties and optimization of dosage forms. The ability to optimize the release kinetics is a key factor in the endeavour of increasing pharmaceutical availability. The optimization may be done by a suitable choice of the dosage form or by clever distribution of the drug in the auxiliary substances or even by using an automatically working drug delivery device. This paper describes a model-based analysis and preparation of hydrogels. The following composition was used in the experiment: Chitosan – the gel creating basis; polymer, chlorhexidine – the drug; dodecyltrimethylammonium bromide – the auxiliary substance and surfactant. The release kinetics were studied at three temperatures and were evaluated by using several models (zero order, pseudo-first order, first order, Higuchi, Hixon Crowell, Weibul distribution and Korsmeyer-Peppas). It was found that the best fitting model of the drug rel...