Development, characterization, and in-vivo evaluation of a novel chitosan: Guar gum particulate system for colonic release of triamcinolone

Abstract

Drug delivery systems based on carbohydrate polymers have shown promising results for the colonic release of drugs due to the selective degradation by the local microbiota and physical resistance to the physiological conditions of the gastrointestinal tract. This work aimed to obtain and characterize a novel particulate system (PS) based on chitosan and guar gum polymers (CHI-GG) for the release of triamcinolone (TRI) and evaluate the in vivo anti-inflammatory activity of ulcerative colitis. PS were prepared by combining coacervation and spray drying techniques using different CHI-GG and drug-polymer ratios. For obtained, PS CHI-GG-TRI systems were characterized. To evaluate the in vivo activity of PS containing TRI, we used Wistar rats to observe the anti-inflammatory response in macroscopic and microscopic parameters of the intestinal mucosa. PS-TRI demonstrated improvements in the aspects related to reducing adverse effects of the drugs when administered in their free form. PS-TRI release occurred in only 69 % of the active in 24 h; the macro and microscopic parameters and the activity of the experimental ulcerative colitis were softened, and an excellent potential anti-inflammatory effect was observed. Infrared data evidenced the incorporation of TRI on the PS. DSC analysis showed the compatibility between TRI and the polymers of the PS. The release kinetics showed an initial burst release of TRI followed by a controlled release profile for up to 30 h. Therefore, a new PS for TRI release was obtained that can swell and control TRI release and that showed anti-inflammatory activity in an animal model, also reducing adverse effects present in conventional treatments.