The specific aim of this study was to develop a pH independent controlled release system for the basic drug, theopylline. The release of the drug was investigated in vitro from hydrophilic swellable matrices composed of hydroxyethyl cellulose and Eudragit S100. The micro-environmental pH of the hydrated gel layer of the matrices was manipulated by the addition of fumaric acid. It is expected th...

Voclosporin is a highly potent, new cyclosporine-A derivative that is currently in Phase 3 clinical trials in the USA as a potential treatment for inflammatory diseases of the eye. Voclosporin represents a number of very sparingly soluble drugs that are difficult to administer. We therefore selected it as a model drug that is dispersed within amphiphilic polymer matrices, and investigated the c...

This paper reviews the use of texture analysis in studying the performance of hydrophilic matrices of highly soluble drugs and different types of excipients (i.e. water-soluble, water-insoluble and swellable, and water insoluble and non-swellable). Tablets were prepared by direct compression, and their swelling and erosion in presence of these different excipients were assessed with the help of...

We present a new route for mass-production of B and P codoped all-inorganic colloidal Si nanocrystals (NCs) from hydrogen silsesquioxane (HSQ). Codoped Si NCs are grown in glass matrices by annealing mixture solutions of HSQ and dopant acids, and then extracted from the matrices by hydrofluoric acid etching. The free-standing NCs are dispersible in methanol without any surface functionalization...

Hydrophilic matrices are widely used for extended release drug delivery, with hypromellose (HPMC) being a popular rate-controlling carrier. The FDA has recently issued an alert regarding the potential negative influence of alcohol on extended release dosage forms. The aim of this study was to investigate the hydroalcoholic solution effect on hydration, gel formation and drug release from HPMC m...

In this study, attempts were made to evaluate the effect of various acrylic acid based Carbopols on the release profile of a beta-adrenoreceptor blocking drug, propranolol HCl, from matrix-type tablets invitro. For this purpose, tablets containing 160 mg of propranolol HCl along with various amounts of Carbopols 934 (C934), 971 (C971), 974 (C974) and Pemulen (Pem) were prepared using the wet gr...

the effect of different kinds of surfactants in various concentrations incorporated in an inert matrix, on the release of procainamide hydrochloride, as a cationic model compound, was investigated in this study. sodium lauryl sulfate and sodium stearate as anionic surfactants, cetyl pyridinium chloride and cetyltrimethyl ammonium bromide as cationic and span 60 and tween 80 as non-ionic surfact...

The effect of different kinds of surfactants in various concentrations incorporated in an inert matrix, on the release of procainamide hydrochloride, as a cationic model compound, was investigated in this study. Sodium lauryl sulfate and sodium stearate as anionic surfactants, cetyl pyridinium chloride and cetyltrimethyl ammonium bromide as cationic and span 60 and tween 80 as non-ionic surfact...

The effect of different kinds of surfactants in various concentrations incorporated in an inert matrix, on the release of procainamide hydrochloride, as a cationic model compound, was investigated in this study. Sodium lauryl sulfate and sodium stearate as anionic surfactants, cetyl pyridinium chloride and cetyltrimethyl ammonium bromide as cationic and span 60 and tween 80 as non-ionic surfact...