Polysaccharide based colon-specific nano particulate drug delivery system

Abstract

Natural polysaccharides are now extensively used for the development of solid dosage forms for delivery of drug to the
colon. The rationale for the development of a polysaccharide based Nano particulate delivery system for colon. Various
approaches used for targeting the drugs to the colon include, formation of a prodrug, multi-coating time-dependent
delivery systems, coating with pH-sensitive polymers, pressure dependent systems, and the use of biodegradable
polymers. In particular, polysaccharides seem to be the most promising materials in the preparation of nanometeric
carriers. In this review, four mechanisms are introduced to prepare polysaccharides-based nanoparticles, that is, covalent
crosslinking, ionic crosslinking, polyelectrolyte complex, and the self-assembly of hydrophobically modified
polysaccharides. The approaches utilizing polysaccharides for colon-specific delivery are fermentable coating of the drug
core, embedding of the drug in biodegradable matrix, formulation of drug-saccharide conjugate (prodrugs). A large
number of polysaccharides have already been studied for their potential as colon-specific drug carrier systems, such as
chitosan, pectin, chondroitin sulphate, cyclodextrin, dextran, guar gum, inulin, amylose and locust bean gum. Recent
efforts and approaches exploiting these polysaccharides in colon-specific drug delivery system.