The aim of the present study was to compare some physicochemical properties of guar gum samples from different sources and thus to investigate the suitability of these samples for the formulation of either prolonged-release or colon-specific dosage forms. Twelve different guar gum samples from India, Pakistan and the USA were used. Theophylline was chosen as a model drug. The flow type of the guar gum samples was determined as pseudoplastic. The viscosity and the particle size of the guar gum samples were found to be the main parameters which could affect the drug release from matrix tablets. All of the guar gum samples are suitable for use in the preparation of prolonged-release matrix tablets. But, three of them, obtained from India and the USA, may be potentially the most suitable guar gum samples for the preparation of colon-specific dosage forms.
展开▼
