Synthesis and engineering of sodium alginate/inulincore-shell nano-hydrogels for controlled-release oral delivery of 5-ASA

Özet

Protectionof drug molecules fromdigestive enzymes and providing their controlled release at the site of intestinal inflammationarethe most important aims of oral nano drug delivery systems (NDDSs).Encapsulation and controlled release of 5-aminosalicylic acid (5-ASA), which is a well-known anti-inflammatory drug, for effective treatment of Crohn’s disease, ulcerative colitis and inflammatory bowel disease (IBD)wereaimed in this study. For the preparation of core-shell structured NDDSs, 5-ASA loaded sodium alginate (Na-Alg) coreswith negative surface charge were prepared by calcium chloride crosslinking of Na-Alg and subsequentlycoatingwith quaternized inulin (QIn) viaCoulomb interaction. As a shell layer, QIn was separately synthesized by quaternization of inulinwith glycidyl trimethylammonium chloride (GTMAC). While the crosslinked Na-Alg core is responsible fortheprotection of 5-ASA from acidic pH in stomach, quaternized inulin shell, known to be highlymucoadhesive, was implemented for digestion by the intestinal flora providing controlled release of 5-ASA at inflammation site of small and/or large intestine.Characterization of NDDSs was carried out using GPC, FT-IR, 1H-NMR and SEMtechniques. Ideal slow release of 5-ASA was obtainedwith thefrom spherical particleshavingcoreandshellsizesof 84-100 and 156-198 nm, respectively.