Optimization for glimepiride dissolution enhancement utilizing different carriers and techniques

Abstract

The present work is a comparative study that matches between carriers and techniques used to prepare solid mixtures with glimepiride. The study is directed towards elucidation of the most promising carrier capable of highly improving drug dissolution along with the most successful technique used for drug formulation. Mixtures were tested for drug content and dissolution. The most optimum formulae were characterized by DSC, IR and XRPD. Kinetic treatment of dissolution data was performed for physical and co-ground mixtures, solid dispersions and their adsorbates, triple solid dispersions and their adsorbates, microwave generated or treated solid dispersions. Results revealed that enhancing effect mostly reached maximum with ternary solid dispersion adsorbate (TSDads). The latter technique demonstrated a dramatic increase in drug dissolution rate which was reflected in the shortest half-life for most carriers at variable degrees. The highest dissolution rate was attained with pregelatinized starch and decreased to variable degrees with remaining carriers. Differences were ascribed to chemical nature as well as relative water solubility of carriers. The combined effects of incorporating surfactants, polymers and adsorbents to glimepiride contributed together to improve wetting, reduce crystallinity and caused substantial increase in the surface area which made TSDads the most promising technique for enhancing dissolution of glimepiride.