Polysaccharide-Based Colon-Targeted Drug Delivery System

Polysaccharide-based colon-targeted drug delivery systems (CDDS) have gained significant attention for the localised management of colonic disorders, including inflammatory bowel disease and colorectal cancer. Conventional oral delivery systems often lead to premature drug release and systemic exposure, thereby limiting therapeutic efficacy. In contrast, polysaccharides remain intact in the upper gastrointestinal tract and are selectively degraded by the colonic microbiota, thereby enabling site-specific drug release.

This review outlines the physiological and microbial basis of colon targeting and critically examines key polysaccharides and their derivatives used in CDDS. Major drug release mechanisms, including microbial, enzymatic, pH-dependent, and time-controlled systems, are discussed, with emphasis on multi-trigger strategies for improved targeting reliability.

Recent advances in nanocarrier systems and stimuli-responsive formulations highlight the evolving potential of these platforms. However, challenges such as microbiota variability, formulation reproducibility, and regulatory limitations continue to hinder clinical translation.

Overall, polysaccharide-based CDDS offer a rational and promising approach for precise colonic drug delivery, with future progress dependent on overcoming current translational barriers.