Polymorphism and drug release behavior of spray-dried microcapsules of sulfamethoxazole with polysaccharide gum and colloidal silica

Abstract

Sulfamethoxazole microcapsules with polysaccharide gum, i.e. xanthan gum and guar gum, were prepared by employing a spray drying technique. The aqueous or the ammonium hydroxide solution of the gum containing the drug with or without colloidal silica was atomized with a centrifugal wheel atomizer rotated at 40000 rpm into a drying chamber held at 140±10°C. By formulation with colloidal silica, particle size of the resultant product increased, leading to improve the flowability and packability for the tableting. Polymorphic sulfamethoxazole mixture of Form I, II and III was produced in the formulation with cellulose acetate