Bioefficacy of budesonide loaded crosslinked polyeletrolyte microparticles in rat model of induced colitis

A targeted delivery system for inflammatory bowel diseases, chitosan-Ca-alginate microparticles efficiently loaded with budesonide (BDS), were designed using one-step spray-drying process. They were eudragit coated and examined for in vivo efficacy. Experimental colitis was induced by rectal instillation of 2,4,6 trinitrobenzene sulphonic acid (TNBS) into male Wistar rats. Drugs were administered by oral gavage daily for 5 days. Colon/body weight ratio, gross morphological and histological evaluation, and clinical activity score were determined as inflammatory indices. Individual clinical and histological evaluation showed that colitis severity was suppressed the most greatly in order BDS < BDS/C-Ca-A < E-BDS/C-Ca-A. Clinical activity score decreased in the same order. Statistical analyses of total score points indicate that the incorporation of BDS in microparticles had significant differences in favor of efficacy of designed delivery system with mucoadhesive and controlled release properties (one-way ANOVA, P<0.05). The results established the prediction by previous in vitro studies.