Development of mesalamine loaded-fenugreek gum decorated pectin microspheres for colonic drug delivery: Ex-vivo and in-vitro characterizations

Mesalamine (MES) is a preferred therapeutic agent for managing various colon disorders, including inflammatory bowel diseases (IBD). However, conventional oral dosage forms of MES face significant limitations, which reduce their effectiveness in managing these conditions. To overcome these challenges, advanced dosage forms of MES are essential. Fenugreek gum (FG), a natural polysaccharide with non-toxicity, ease of synthesis, biodegradability, and biocompatibility, was selected as a key component for developing a novel delivery system. Calcium ion crosslinked MES-incorporated FG-decorated pectin microspheres (FG@MES/PM) were successfully designed for colon-specific drug delivery using an ionotropic gelation technique. The microspheres exhibited favorable physicochemical characteristics, including a particle size of 586nm, a polydispersity index of 0.348, an entrapment efficiency of 85.20±1.02%, and a drug content of 98.52±0.96%. Ex vivo mucoadhesion tests demonstrated strong mucoadhesive properties, highlighting the potential of FG@MES/PM to adhere effectively to the colonic mucosa. In vitro drug release studies showed a modified release profile, with 99.02±1.80% MES released over 24h. Release kinetics analysis confirmed that FG@MES/PM followed the Higuchi matrix model (R²=0.9867), indicating diffusion-controlled release. The drug release mechanism was characterized as anomalous (non-Fickian) transport, with a release exponent (n) of 0.563. Overall, FG@MES/PM demonstrated promising potential for colon-specific drug delivery, offering sustained release and enhanced mucoadhesion. This study underscores the utility of FG for developing advanced drug delivery systems targeting the colon. Future research should explore the broader application of FG and similar natural polysaccharides in designing efficient and biocompatible colon-targeted formulations to improve therapeutic outcomes for IBD and related conditions.